Case studies offer essential insights into the practical application of cyber forensics, demonstrating how theoretical concepts are utilized to combat complex cyber threats. By examining incidents, such as ransomware attacks or supply chain breaches, investigators can identify weaknesses in current cybersecurity frameworks and formulate more effective defensive strategies. These real-world instances demonstrate the forensic techniques employed and underscore the significance of prompt detection, comprehensive investigation, and post-incident evaluation to avert future breaches. This case study examines the intricacies and obstacles organizations encounter in addressing cyber-attacks and illustrates how utilizing sophisticated forensic tools and methodologies in cloud environments such as Azure can alleviate damage, restore data, and strengthen defenses against emerging threats. This section delves into the practical applications of cyber forensics by analyzing detailed case studies.
7.1. Forensic Investigation of a Ransomware Attack on an Azure-Hosted Service
A medium-sized enterprise encountered a significant disruption due to a ransomware attack that encrypted vital data across its Azure-hosted services. This incident hindered operational capabilities, and severe data leakage risks were also posed. Consequently, a forensic investigation team was engaged to analyze the breach, pinpoint the attack vectors, and devise strategies to prevent future incidents.
Figure 2 comprehensively illustrates the forensic analysis process undertaken in response to a ransomware attack on Azure-hosted services. The systematic approach, from the initial engagement of the forensic team through to the final mitigation and prevention strategies, is outlined in the
Figure 2:
In this case study, the forensic team within Azure Sentinel employed a structured, multi-step analysis to investigate a ransomware breach initiated via a phishing email. The investigation was conducted through systematic log consolidation, targeted KQL queries, and behavioral analysis.
7.1.1. Data Collection and Consolidation
The forensic analysis was initiated by identifying key log sources within the Azure environment, which could provide critical insights into the suspected ransomware breach. The primary logs gathered included Azure Activity Logs, Sign-in Logs, and security events. The logs were essential for tracing user and system activities, access attempts, and configuration changes across the environment. Additionally, customized logs were extracted from specific virtual machines linked to the affected systems, with application-level events being captured that could potentially reveal the attacker’s behavior. The data collection process was carried out in phases, beginning with the initial aggregation of log data from each identified source. The native capabilities of Azure Sentinel were configured to automate the aggregation process, thereby ensuring data continuity and real-time updates as new logs were generated. Pre-processing steps were undertaken to maintain consistency across these various log sources. The normalization of timestamp formats, the standardization of field names, and the removal of redundant data entries were involved, which facilitated smoother correlation during analysis. To streamline data ingestion and reduce manual intervention, predefined connectors were set up in Azure Sentinel to continuously collect and update log data from the Azure Activity Logs, security events, and Sign-in Logs. These connectors ensured that up-to-date information was provided by each log source, which allowed for the effective monitoring and analysis of data by the forensic team. A strong foundation for conducting comprehensive forensic investigations with consistent, reliable data was laid by this integration, coupled with automated ingestion.
7.1.2. Specific KQL Queries and Indicators
Suspicious activities linked to the ransomware breach were identified using targeted Kusto Query Language queries within Azure Sentinel. Specific anomalies and indicators of compromise (IoCs) that could signify unauthorized access or malicious activity were detected by crafting these queries.
The primary query focused on unusual login locations to identify logins from regions outside the organization’s expected operational boundaries. The detection of potential account takeovers was facilitated by filtering sign-ins from high-risk geolocations:
The following table represents the output of the query, highlighting users with multiple suspicious sign-in attempts from unexpected regions:
Anomalous login activities were identified by isolating users who accessed the system from unexpected regions outside the operational zones. Multiple logins by
[email protected] from “UnknownRegion1” were noted, which could indicate user travel or credential misuse. Additionally,
[email protected] logged in five times from “SuspiciousRegionX”, flagged in prior threat intelligence. Furthermore,
[email protected] was observed to have eight logins from “HighRiskRegion”, which raises significant concern due to its administrative privileges. Immediate actions were taken, including investigating associated IP addresses for malicious activity, verifying login legitimacy through user travel or VPN logs, and resetting credentials if unauthorized access was confirmed. During the Identification Phase of the forensic workflow, these anomalies were identified, and critical insights were provided for further machine learning-based analysis to mitigate and prevent similar unauthorized access in the future.
The aggregation of login attempts from non-standard locations was conducted, enabling the identification of accounts accessed from unfamiliar or high-risk regions, which may suggest compromised credentials. A further inquiry was directed towards failed login attempts, as it may be recommended that repeated failures indicate brute-force attacks or unauthorized access attempts. Monitoring for a threshold number of failed logins within a specified timeframe allowed for the isolation of accounts experiencing repeated access attempts:
The query was conducted to highlight accounts that exhibited multiple failed login attempts, which may indicate possible brute-force attempts or attempts to access accounts with elevated privileges:
This query analyzes Windows security event logs (Event ID 4625) to detect accounts with an unusually high number of failed login attempts. This pattern often signals brute-force attacks or credential-stuffing attempts where attackers repeatedly try to access an account using guessed or stolen credentials. The query aggregates failed attempts by user account and originating IP address, isolating instances where more than five failures are logged. The results provide critical evidence for identifying unauthorized access attempts, which can help prevent account compromise and inform subsequent forensic analysis.
To detect privilege escalations, the team implemented a query to monitor additions to high-privilege groups, such as administrators or other critical roles. The identification of newly added accounts within privileged groups was facilitated by this query, which serves as a standard indicator of an attacker’s attempt to gain elevated access:
This query was designed to filter for role changes indicating privilege escalation, particularly when new accounts were added to high-level administrative groups:
The output revealed accounts and roles involved in privilege changes, such as
[email protected], where two members were added to the highly sensitive Global Admin role, raising concerns about unauthorized escalation. Similarly,
[email protected] added a member to the Security Group Admin role, suggesting potential lateral movement, while
[email protected] added three members to the Directory Readers role, possibly for reconnaissance. Immediate actions included verifying the legitimacy of added accounts, auditing their activities, and revoking unauthorized access. These findings, aligned with the Identification Phase, provide critical insights for further investigation and correlation with system activity logs to assess potential compromise of sensitive systems.
7.1.3. Steps for Anomaly Detection
The forensic team employed a combination of thresholds, parameters, and behavioral analysis techniques within Azure Sentinel to pinpoint suspicious activities associated with the ransomware attack. Specific detection criteria were set, allowing for systematically isolating abnormal behaviors.
Multiple failed login attempts within a short period may indicate a brute-force attack. The team established a threshold of five failed login attempts within an hour for each account. An alert was triggered if the threshold was exceeded, indicating that the account was potentially compromised. An example of a KQL query is presented below:
Each one-hour time bin counts the number of failed login attempts per account and IP address. Any account that exceeds five failed attempts per hour is flagged for further investigation, which aids in the team’s effective detection of brute-force attempts.
The code for the Anomaly Detection Phase was enhanced by the addition of temporal granularity and contextual parameters, which are intended to improve the precision and relevance of detected anomalies. The bin(TimeGenerated, 1h) function was introduced in the code, allowing for the aggregation of failed login attempts into specific time intervals. This enables the detection of rapid, concentrated bursts of activity that are characteristic of brute-force or credential-stuffing attacks. It is allowed for forensic teams to identify not just overall patterns of suspicious behavior but also time-bound anomalies that may indicate an ongoing attack. Additionally, it has been observed that filtering by specific thresholds (e.g., more than five failed attempts per hour) results in noise reduction, with a focus placed on significant deviations from baseline behavior. This query is made more effective for uncovering sophisticated, time-sensitive threats, such as targeted account compromise attempts, and actionable insights are provided for deeper investigation and automated alerting.
Logins from various geographic locations within a brief time frame are considered a strong indicator of account compromise. This query identifies accounts logging in from regions not commonly associated with the user’s activity. An example of a KQL query is presented below:
Login events were grouped by user and time bin, followed by creating a list of unique login locations for each hour. If a user logged in from multiple locations within a one-hour timeframe, the account was flagged. This method highlights impossible or suspicious travel patterns, revealing the potential for account takeovers.
Unexpected additions to privileged groups, such as “Domain Admins” or “Enterprise Admins”, indicate attempts at privilege escalation. The team created a query to monitor modifications within the group, specifically focusing on tracking new accounts added to these high-privilege groups. An example of a KQL query is presented as follows:
This query filters operations involving adding members to specific high-privilege roles. Each flagged account was scrutinized for signs of privilege escalation or unauthorized access.
The team established baselines for each account’s typical login patterns to capture anomalous behavior. Standard login times, locations, and access frequency for each user were identified by examining logins over two weeks. A review was initiated for deviations from this baseline. An example of a KQL query is presented below:
Each user’s average login time was established over 14 days, and recent logins (within the past day) were compared against this baseline. Logins recorded more than three hours outside the user’s typical range were flagged as anomalies:
The login behaviors were analyzed by comparing recent login times to the average login time of each user over the past 14 days. Logins that occurred significantly outside the user’s typical time frame were identified, utilizing a deviation threshold of three hours. For example, it was noted that
[email protected] logged in at 3:15 a.m., which was significantly earlier than the average login time of 10:00 a.m., suggesting that unauthorized access or unusual activity may have occurred. It was observed that
[email protected] logged in at 10:30 p.m., which deviated from the average of 3:00 p.m., while
[email protected] logged in at 1:10 a.m., which was outside the normal range of activity for this high-value account. Further investigation is warranted for these anomalies to validate the legitimacy of the logins and assess potential threats. Deviations in login patterns were focused on, enhancing anomaly detection by uncovering behavioral outliers that could signify account compromise or insider threats.
The combination of threshold-based queries with behavioral baselines effectively narrowed down potential indicators of compromise by the forensic team. These methods highlighted critical points for investigation and provided a reproducible framework for detecting anomalies tied to account takeover, brute-force attacks, and privilege escalation.
7.1.4. Phishing Email Analysis
The initial point of compromise in the ransomware attack was identified, leading the forensic team to investigate the presence of phishing emails, which are frequently utilized to gain unauthorized access. Several steps were involved in this analysis, beginning with the detection of phishing emails and then the attacker’s use of stolen credentials.
The phishing email was identified through a thorough examination of email logs within Microsoft 365 conducted by the team. Potential phishing messages were narrowed down by filtering for emails that contained known malicious indicators, such as links or attachments that threat intelligence feeds had previously flagged. An example KQL query is provided in Microsoft 365 Defender:
This query was designed to identify emails classified as phishing attempts, with a particular emphasis on those that contained high-risk attachments or malicious URLs. Once identified, emails, particularly those sent to users in sensitive roles, were flagged for further inspection:
Phishing emails flagged with “Phish” in their threat types were identified by the query, with a focus on those containing high-risk attachments such as .zip, .exe, or .docm, or malicious URLs. An email was received by
[email protected] from
[email protected] containing a .zip file and a suspicious URL, while
[email protected] was targeted by
[email protected] with an executable attachment (.exe). A phishing email was received by
[email protected] from
[email protected], which contained a .docm file and a phishing URL. Potential threats were highlighted by these findings, warranting immediate actions such as the blocking of sender domains, the quarantining of emails, and the alerting of recipients to mitigate risks like credential theft or malware infections.
Following the identification of the phishing email, the subsequent step was to trace the utilization of stolen credentials through this initial compromise. Login events associated with the user who received the phishing email were examined, focusing on tracking IP addresses, locations, and times of login attempts. An example of a KQL query that was utilized for tracking login patterns is presented below:
The login attempts associated with the compromised account were isolated and grouped by location and IP address. Following the phishing compromise, anomalous login locations or frequencies revealed unauthorized access patterns.
The team traced lateral movements within the network, with evidence of compromised credentials, through monitoring abnormal access or privilege escalation activities associated with the compromised account. For instance, any unusual additions to privileged groups by this account were identified as indicators of further compromise. An example KQL query for changes in privileged groups by a compromised account is presented below:
This query explicitly tracks privilege changes initiated by the compromised user. The addition of accounts to high-level roles, such as administrative groups, was flagged, as it may indicate attempts by an attacker to escalate privileges.
To strengthen the analysis, the email metadata and headers were examined to verify the origin and authenticity of the phishing email. Analyzing fields such as Received, Return-Path, and Message-ID allowed the confirmation of the email’s external origin and identified any spoofing attempts. The validation of the compromised account access was found to be related to the phishing vector.
7.1.5. Reproducible Timeline or Workflow
The forensic team documented a detailed timeline and workflow outlining the entire process, from data collection to incident confirmation, to ensure the investigation could be replicated and validated. The structured approach facilitated explicit event tracking and allowed other investigators to follow the same methodology in similar breach scenarios.
The investigation was initiated by configuring Azure Sentinel to ingest data from various sources, including Azure Activity Logs, Sign-in Logs, security events, and custom logs from relevant virtual machines. Data ingestion automation was implemented to capture new logs in real time, ensuring that all pertinent activity was documented as the investigation progressed. (It should be confirmed that all data sources were connected and actively feeding into Azure Sentinel before the initiation of any queries. The comprehensive visibility of the environment was ensured from the outset.)
The team executed targeted KQL queries to identify specific indicators of compromise with data in place. Queries focused on failed login attempts, privilege changes, and unusual login locations. The detection of each anomaly was accompanied by timestamping and logging, which formed the initial indicators of potential compromise. Flagged anomalies, including suspicious logins or privilege escalations, should be cross-referenced with known attack patterns or indicators of compromise (IoCs) to ensure alignment with the case-specific indicators identified in the data.)
The origin of unusual login activities was traced back to a phishing email by analyzing Microsoft 365 email logs. The metadata and header information of the phishing email were examined to validate its role in the attack. Upon identification, the team tracked the use of stolen credentials within the compromised account, with monitoring conducted for signs of lateral movement and privilege escalation. (It should be verified that the compromised account demonstrated a precise sequence of events originating from the phishing email. The phishing email was established as the initial breach point, and the sequence of unauthorized access attempts was validated.)
Access to high-value resources was subsequently gained using the compromised credentials. Changes to privileged groups and lateral movements across systems were monitored, allowing for the establishment of how the attacker advanced within the network. (It is to be confirmed that changes in group memberships or resource access were directly correlated with the activities of the compromised account. The link between the initial phishing compromise and subsequent unauthorized access attempts was reinforced.)
The forensic team compiled a timeline to document the attack sequence clearly, which included each major event: initial phishing email compromise, first unauthorized login, privilege escalations, and any lateral movements. The timeline was composed of timestamps, log sources, query outputs, and validation points for each phase. (The timeline will be subjected to a final review, incorporating cross-validated findings from all queries and log sources. It should be ensured that the collected log data or query results directly support each event in the timeline.)
The investigation was organized into a reproducible timeline with defined validation points, ensuring that each phase was thoroughly documented and could be independently verified by the team. This structured workflow facilitated a transparent forensic investigation, allowing for precise evidence tracking from the initial compromise to the full breach confirmation, thereby providing a robust framework for future incident response efforts.
7.1.6. Conclusions Based on Findings
Upon completing the investigation, the forensic team reached conclusions based on the evidence gathered, corroborated findings, and observed indicators of compromise (IoCs). The systematic approach employed throughout the investigation facilitated the connection of each anomaly with the attack timeline, establishing a transparent and verifiable narrative of the incident.
Each identified event—from the initial compromise of the phishing email to privilege escalations and lateral movements—was cross-referenced with relevant log data to ensure consistency across sources. For instance, the phishing email identified in Microsoft 365 was found to be directly linked to subsequent unauthorized login attempts that Azure Sentinel’s Sign-in Logs flagged. A clear cause-and-effect relationship was established by this correlation, with the phishing email being identified as the point of initial compromise.
Compromised credentials obtained through the phishing email were traced to privilege escalations, during which the attacker added accounts to high-privilege groups. Sequential analysis confirmed that the attacker leveraged stolen credentials to gain additional access, resulting in a coherent narrative of the attack progression.
Focusing on specific anomalies could help detect similar phishing-based compromises early. The team’s effective tracing of unauthorized access patterns was facilitated by monitoring email logs for flagged phishing attempts and behavioral analysis of account activity. Other organizations can replicate this approach by implementing similar logging and query strategies, particularly identifying deviations from user baselines and tracking changes to high-privilege accounts.
The team concluded that a proactive approach to anomaly detection is recommended, emphasizing the importance of continuous monitoring and data correlation across Microsoft 365 and Azure Sentinel. Establishing behavioral baselines for high-value accounts and setting alert thresholds for privilege changes were highlighted as critical early breach detection and containment strategies.
The team proposed further refinement of the existing detection rules and thresholds to improve incident response readiness, emphasizing monitoring abnormal login attempts, multi-region access within short intervals, and privilege changes. Furthermore, integrating threat intelligence feeds was advised to identify known phishing domains or IP addresses associated with malicious activities, which could enhance the early detection of phishing attacks.
The team recommended implementing similar workflows and validation steps as standard operating procedures in future incidents, enhancing repeatability and ensuring a structured, comprehensive response.
After this attack, an overview of the incident was initiated, and the disruption caused by the ransomware was highlighted. Key phases were progressed through, including data collection, in-depth Azure tool analysis, and identifying the initial attack vector via phishing. The containment and mitigation efforts are detailed in subsequent sections, including resetting compromised credentials and implementing just-in-time VM access. The outcomes and recommendations are highlighted in the flowchart, which includes enhancements in security training and the integration of advanced threat protection features. Proactive monitoring and regular security assessments are underscored to fortify the organization against future threats. This visual representation effectively encapsulates the entire process, which provides a clear roadmap of the actions taken and the lessons learned from the cybersecurity incident.
The initial attack vector was ascertained, and the subsequent maneuvers executed by the attackers were analyzed. The extent of the impact on the Azure-hosted resources was assessed, and recommendations to address vulnerabilities and enhance the security framework were provided. The goals aimed to provide a comprehensive understanding of the attack’s penetration and progression, evaluate the damage inflicted on the cloud infrastructure, and develop robust measures to bolster the enterprise’s cybersecurity defenses against future threats.
A systematic approach was employed in the forensic investigation, utilizing Azure’s suite of forensic tools and encompassing several vital phases. Initially, Azure Activity Logs were gathered to trace the operations performed by the attackers. Detailed telemetry data indicative of potential malicious activities was captured using Azure Monitor Logs, and snapshots of affected virtual machines were taken to preserve their states during the attack for further offline analysis. Log data were consolidated and analyzed using Azure Sentinel during the analysis phase. The team employed the KQL to identify anomalies, including irregular login attempts and unexpected external connections. A comprehensive timeline of events was developed to delineate the sequence of attacker activities, from the initial breach through network lateral movements to the deployment of ransomware.
The forensic analysis indicated that the initial breach was facilitated by a phishing email that compromised an employee’s credentials, which were subsequently exploited due to inadequate conditional access policies to obtain elevated privileges. Immediate strategies for containment and mitigation were recommended, including resetting compromised credentials, enforcing multi-factor authentication for all users, and updating firewall rules to limit unusual outbound traffic. Furthermore, it was advised that Azure Security Center’s just-in-time VM access feature be implemented to minimize the attack surface by strictly limiting VM access to necessary instances.
The investigation determined that the root cause of the breach was a combination of social engineering through phishing and misconfigured security controls. Due to rapid detection and responsive measures, the impact of the ransomware was confined to a limited portion of the company’s Azure environment. To prevent future incidents, several recommendations were made, including enhanced security training for employees, routine audits of Azure configurations, and the integration of sophisticated threat protection features within Azure. These measures aim to strengthen the organization’s security posture and reduce the likelihood of similar breaches in the future.
The investigation underscored the importance of proactive monitoring and anomaly detection using Azure tools, which are essential for the early identification of potential threats. Additionally, it highlighted the need for regular security posture assessments using the Azure Security Benchmark to ensure compliance with optimal security practices across all Azure resources. These lessons learned emphasize the necessity of maintaining vigilance and adhering to best practices to safeguard against future cyber threats effectively.
7.2. Enhancing Azure Forensics with Artificial Intelligence
Organizations’ migration of critical infrastructure to the cloud has resulted in an exponential increase in the complexity and volume of security data, necessitating a more sophisticated approach to forensic analysis. It has been observed that traditional rule-based security mechanisms frequently encounter challenges in adapting to the dynamic and evolving nature of cyber threats within cloud environments, where subtle behavioral changes and low-frequency anomalies may serve as indicators of sophisticated attacks. The challenges presented are addressed using artificial intelligence and machine learning, which are recognized as essential tools for modern forensic investigations. Security teams facilitate detection and response to incidents in near real-time with increased accuracy.
The cloud-native Security Information and Event Management and Security Orchestration, Automation, and Response platform, Azure Sentinel, is enhanced through AI-driven capabilities, improving the forensic workflow. Integrating data from multiple sources, applying machine learning models for adaptive anomaly detection, and leveraging advanced analytics through Azure Machine Learning (Azure ML) Studio result in a comprehensive and proactive approach to threat detection and incident response by Azure Sentinel.
The application of AI-enhanced forensic capabilities is demonstrated by presenting a case study involving a sophisticated security incident within a financial organization. In this scenario, an attacker gained unauthorized access to a high-value account (
[email protected]) through a phishing email. Subsequently, suspicious activities were observed, including anomalous logins from unusual locations and attempted privilege escalation.
The forensic investigation was conducted across three primary stages, with AI-driven tools in Azure Sentinel being utilized to detect, analyze, and respond to the incident.
Data Collection and Aggregation: The investigation was initiated through the collection of data from various sources, which included Azure Activity Logs, Azure Monitor, and Microsoft 365 logs. These sources provide detailed records of login attempts, access control changes, and system performance metrics. The centralization of these data in Azure Sentinel resulted in a unified view of the environment for the forensic team, which facilitated the identification of suspicious patterns that may have remained undetected in isolated data silos.
Machine Learning Models for Anomaly Detection: Data aggregated in Azure Sentinel established behavioral baselines for the compromised account and other critical entities by applying machine learning models. Sentinel’s built-in anomaly detection models were designed to identify deviations in login times, geographic locations, and access frequency, flagging unusual activities that may indicate potential unauthorized access. In this case, the anomaly detection models quickly highlighted the unusual login behavior and privilege escalation attempts associated with the compromised account.
Advanced Anomaly Detection with Azure Machine Learning Studio: The forensic team in Azure Machine Learning Studio developed a custom anomaly detection model to enhance detection accuracy further. The model based on Isolation Forests was tailored to detect low-frequency anomalies specific to the organization’s operations. The model was deployed as a real-time scoring endpoint, allowing for the continuous scoring of new login events for potential compromise by Azure Sentinel, thereby enhancing the team’s detection of complex or previously unknown attack patterns.
This case study explores Azure Sentinel’s AI capabilities, highlighting the empowerment of forensic teams to adapt to evolving threats, respond to incidents with agility, and improve the overall security posture of cloud-centric environments. This process establishes the critical role of each component of the AI-enhanced forensic workflow—data collection, anomaly detection, and custom model deployment. Actionable insights and automated responses were provided to forensic investigators, significantly reducing the time required to detect and mitigate security incidents.
As demonstrated in this case study, this structured and adaptive approach enables organizations to leverage Azure Sentinel and Azure Machine Learning Studio to transform forensic practices from reactive to proactive. A resilient and scalable defense framework was built, which can address sophisticated threats in today’s cyber landscape. Azure Sentinel and Azure Machine Learning Studio are fundamental parts of the Azure AI-enhanced cyber forensic investigation in Azure, as shown in
Figure 3:
The process was initiated by collecting data from Azure Activity Logs and Azure Monitor, which record detailed information regarding user and system activities. The data were aggregated and processed through Azure Data Factory, a pre-processing step that prepares the data for further analysis. The data were directed to the ML Learning Studio, subjected to unsupervised and supervised learning techniques. Unsupervised learning algorithms detected patterns and anomalies without prior data labeling. In contrast, supervised learning models classified these anomalies into predefined categories, such as potential security threats. The outcomes of these analyses were subsequently integrated into Azure Security Center and Azure Sentinel. Azure Security Center utilized the information to enhance threat protection and improve security management across Azure services. The refined data were used by Azure Sentinel, a cloud-native SIEM system, to monitor, detect, and respond to threats in real time, thereby ensuring a comprehensive and proactive cybersecurity posture. The detection and response to potential cyber threats are streamlined through this integrated approach, while resource allocation and strategic focus within the firm’s cybersecurity operations are also optimized.
7.2.1. Data Collection Procedures
Practical forensic analysis within cloud environments initiates the systematic collection and aggregation of data from diverse sources. Azure Sentinel centralizes security-related telemetry by aggregating logs from various cloud-native and hybrid resources, including Azure Activity Logs, Azure Monitor, Microsoft 365, and other critical sources. The centralization of data collection is essential for providing a holistic view of user activities, system events, and network interactions, enabling a more complete and accurate forensic investigation.
Records of all changes to Azure resources, including administrative actions, access modifications, and resource creation or deletion events, are provided by Azure Activity Logs. The critical nature of these logs for tracking configuration changes, identifying unauthorized administrative actions, and pinpointing potential attack vectors within the Azure environment is emphasized. For example, the attempt to escalate privileges by modifying role assignments can be traced through the operation records in Azure Activity Logs. An example KQL query is provided for the identification of suspicious role assignment changes:
This query isolates successful role assignment changes, filtering out authorized users. It is beneficial for detecting unauthorized role modifications that may indicate privilege escalation attempts:
Unauthorized role assignment changes in Azure resources were detected by filtering for successful “MICROSOFT.AUTHORIZATION/ROLEASSIGNMENTS/WRITE” operations that were not performed by known authorized users. Potential privilege escalation activities were highlighted by the results, including modifications of roles in resourceGroup1 by
[email protected], changes made in resourceGroup2 by
[email protected], and updates to roles in resourceGroup3 by
[email protected]. It may be indicated by these unauthorized actions that accounts have been compromised or malicious activity has occurred, necessitating immediate investigation to validate the legitimacy of the role assignments and revoke unauthorized changes. Critical security risks are pinpointed by this query, with support provided for the forensic workflow during the Identification Phase through the flagging of anomalous privilege changes for further investigation and mitigation.
Azure Monitor provides a comprehensive suite of logs capturing resource performance metrics, diagnostic data, and health status across Azure resources. Forensic purposes can be served by configuring Azure Monitor to capture specific events, including high CPU usage, network traffic spikes, or unauthorized access attempts on virtual machines (VMs), which may indicate suspicious activity. For instance, if an attacker attempts to exfiltrate data, identifying abnormal network traffic may be facilitated by analyzing the Network Security Group (NSG) flow logs that Azure Monitor provides. An example KQL query for the detection of abnormal network traffic through Azure Monitor is provided below:
This query indicates the detection of inbound denied traffic from external IP addresses, which may suggest attempted reconnaissance or access from suspicious sources. Unusual traffic patterns were identified, allowing the forensic team to focus on high-risk IPs and potentially compromised resources:
High volumes of denied inbound traffic targeting Azure resources were identified by this query, with a focus on remote IPs that generated over 100 denied requests within one-hour intervals. The potential reconnaissance or attack attempts are highlighted by the results, with 150 denied requests generated by 203.0.113.42 at 10:00 a.m., 200 by 198.51.100.77 at 11:00 a.m., and 120 by 192.0.2.24 at 12:00 p.m. It is suggested that scanning activities or unauthorized access attempts were blocked by network security rules. Immediate actions were taken, including the investigation of flagged IPs for malicious activity, the enhancement of network security rules, and the monitoring of any associated suspicious behavior. The Identification Phase is supported by this analysis, which allows for the detection of potential external threats and the mitigation of their impact before successful intrusions can escalate.
User activities within the Microsoft 365 suite, including email access, file downloads, and login attempts, are captured by Microsoft 365 logs. These logs are considered invaluable in forensic investigations, particularly in cases that involve phishing or unauthorized file access. For instance, it can be revealed through Microsoft 365 logs whether a compromised account was utilized to send phishing emails or access sensitive files, thereby assisting in tracing the attacker’s movements and potential data exposure points. An example KQL query for phishing detection in Microsoft 365 logs is provided below:
This query filters emails flagged as phishing attempts. It displays sender and recipient information and associated URLs or attachments. Identifying the initial phishing vector in a compromise and assessing potential exposure is essential.
The integration of on-premises security logs, including Active Directory (AD) logs and endpoint protection data, is supported by Azure Sentinel, thereby facilitating a hybrid view of security events. The value of this capability is particularly noted in environments where Azure Sentinel monitors both cloud-based and on-premises resources. Forensic investigators utilize security events from Active Directory to track user authentication attempts, account lockouts, and changes to group memberships. These logs facilitate the detection of lateral movement or privilege escalation across cloud and on-premises resources. An example KQL query for the detection of suspicious logins in the Active Directory is given below:
This query captures failed remote login attempts, often associated with brute-force attacks or credential-stuffing attempts on accounts accessible from external networks. Such data facilitate the identification of external threats attempting to access internal resources.
7.2.2. Data Transformation and Preparation Using Azure Data Factory
Data must undergo transformation and preparation in AI-driven forensic investigations before effectively utilizing machine learning models. The provision of a powerful, cloud-based ETL (extract, transform, load) service by Azure Data Factory (ADF) is noted, with the automation of data workflows across multiple sources and environments enabled. The orchestration of data movement, transformation, and preparation through ADF allows forensic teams to optimize data for analysis in Azure Machine Learning Studio. This chapter is focused on the support provided by ADF for data readiness in machine learning through transforming, cleansing, and structuring data, which are aimed at enhancing model accuracy and efficiency.
The preparation of data for forensic analysis and machine learning is often characterized by complexity, necessitating a variety of transformations for the standardization and cleansing of data obtained from multiple sources. ADF addresses these challenges through the following capabilities:
ADF enables the seamless integration of data from cloud-based and on-premises sources. Data extraction from services such as Azure SQL Database, Azure Blob Storage, Microsoft 365 logs, and third-party security solutions is supported. Forensic teams utilize this capability to consolidate data from all relevant sources into a single pipeline for consistent processing.
A range of data transformation functions, including data cleaning, aggregation, type conversion, and data enrichment, is provided by ADF and is considered essential for forensic analysis. Raw security logs are refined through these transformations, resulting in a reduction in noise and an improvement in the signal-to-noise ratio. Field formats can also be standardized through transformations, ensuring compatibility with Azure ML Studio models.
Scalability and Scheduling: It has been observed that data workflows within ADF can be scheduled to execute at defined intervals or triggered in real time. The critical nature of this scheduling capability in forensic analysis is highlighted by the necessity for continuous data preparation, which ensures that machine learning models are provided with the latest data. The scalability of ADF enables the processing of large volumes of forensic data without compromising performance.
In the forensic workflow, a typical ADF pipeline is characterized by a series of transformation steps employed to prepare data for utilization in anomaly detection models. An example of a pipeline designed to transform login event data is presented, which includes steps for data cleaning, normalization, feature engineering, and storage in Azure Blob Storage for access by Azure ML Studio. A pipeline that prepares data for a machine learning model to detect abnormal login activities is presented.
The extraction of login data from Azure Activity Logs, Microsoft 365, and external security logs is initiated as the first step. The Copy Data activity of ADF is utilized to move data from these sources into a staging area, typically in Azure Blob Storage. The capture of fields, including UserPrincipalName, Timestamp, Location, and EventType, characterizes the initial extraction. In the Data Cleaning step, invalid or irrelevant records, such as empty fields or failed logs unrelated to security, are removed. Filters can be applied to ADF’s data flows to exclude specific EventType values, ensuring that only relevant login events are processed. Data normalization involves the standardization of time zones to UTC, while the validation of IP addresses is conducted to ensure conformity to correct formats. The normalization of these fields facilitates the alignment of data from different sources. New features were developed to enable anomaly detection within Azure ML Studio. For example, LoginHour is calculated from Timestamp, LoginFrequency is determined by counting occurrences per user, and LocationCategory is derived based on the location field (e.g., trusted or untrusted regions). The transformed data are subsequently loaded into an Azure Blob Storage container. This structured data repository provides the input for training and testing machine learning models in Azure ML Studio.
A transformation example is presented, wherein ADF’s data flow is utilized to standardize timestamps, generate login frequency features, and categorize login locations:
During the data transformation process, timestamps are normalized to a standardized UTC format, which ensures consistency across events from various sources and enables accurate chronological analysis. The specific hour of each login is extracted to facilitate the detection of unusual login times, as certain anomalies may be more detectable based on time-of-day patterns. Additionally, the daily frequency of logins per user is calculated, which serves as a feature for identifying abnormally high login attempts that may indicate potential compromise. Logins are categorized as “Trusted” or “Untrusted” based on predefined trusted regions. This categorization allows for flagging logins from suspicious or unexpected locations, which may necessitate further investigation.
Upon data transformation completion, the pipeline’s final step is loading the prepared data into a storage location accessible by Azure ML Studio, such as Azure Blob Storage or Azure Data Lake. The loading phase renders the transformed data readily accessible for training and inference within machine learning workflows. The automation of this ETL process by ADF results in Azure ML models consistently having up-to-date data, eliminating the need for manual intervention. An example of an automated ADF pipeline configuration for continuous data loading is given below:
This pipeline configuration is designed to facilitate automated, hourly execution of the ETL steps. Raw login data are moved through staging, transformation, and, ultimately, storage for access by ML models.
7.2.3. Utilizing Data for Enhanced Anomaly Detection
Data transformed and standardized by Azure Data Factory enable Azure Machine Learning Studio to be a powerful tool for deploying advanced machine learning models tailored for anomaly detection in forensic analysis. In this scenario, the data prepared by ADF, which included features such as login time, frequency, and geographic categorization, were utilized to train a model that identifies unusual login activities that may signify unauthorized access or potential compromise.
Forensic teams use Azure ML Studio to design, train, and deploy machine learning models that detect patterns and outliers in complex, multi-source datasets. Anomalies that do not fit the established baseline of user behavior can be identified using algorithms such as Isolation Forests or Autoencoders within Azure ML Studio. Login attempts that occur at unusual hours originate from untrusted regions, or exhibit an unusually high frequency may be classified as anomalies, which warrant further investigation.
Transformed data are leveraged by the model to identify deviations in login behavior based on historical patterns, thus enabling a sophisticated layer of security monitoring that surpasses conventional threshold-based alerts. The integration of ADF and Azure ML Studio was observed to enhance the forensic capabilities of Azure Sentinel through the automation of anomaly detection, the reduction in false positives, and the enablement of real-time analysis of potential threats.
Data that have been transformed are stored in Azure Blob Storage, which Azure ML Studio can access them to train the machine learning model. In this case, an Isolation Forest model, well suited for identifying outliers, was employed to detect abnormal login activities. Anomalies were isolated by this model through the random partitioning of data, enabling differentiation between normal and suspicious behaviors without the reliance on labeled training data.
Example Code for Accessing Transformed Data and Training an Isolation Forest Model in Azure ML Studio:
A connection to Azure Blob Storage was established to access the transformed login events data stored in login_events.csv. The cleaned and engineered features created by Azure Data Factory were contained within this CSV file to facilitate preparation for machine learning analysis. Subsequently, relevant features—LoginHour, LoginFrequency, and LocationCategory—were selected as inputs for the model. These features were selected due to their ability to capture essential behavioral attributes of user login activity, enabling the model to establish standard behavior patterns and detect deviations.
An Isolation Forest model was initialized with a contamination level of 0.01, indicating that approximately 1% of the data are expected to be anomalous. The selected features were utilized for training this model, facilitating the identification of outliers by isolating observations that deviate from the baseline of regular activity. Following the training process, the model scores each data point, with a score approaching −1 indicative of a greater likelihood of abnormal behavior. Anomalies identified through observations were isolated in a separate dataset for further analysis, thereby providing forensic investigators with targeted insights into potentially suspicious login activities:
This Python code demonstrates how to use an Isolation Forest machine learning model to detect anomalies in login behavior. The transformed data, stored in Azure Blob Storage, were accessed and loaded into a Pandas DataFrame. Key features, including LoginHour, LoginFrequency, and LocationCategory, were used to train the model. The Isolation Forest algorithm assigned anomaly scores to each record, with lower scores indicating higher suspicion levels. For example,
[email protected] logged in at an unusual hour (3 a.m.) with a high login frequency from an untrusted location, resulting in an anomaly score of −0.75. Similarly,
[email protected] exhibited an unusually high login frequency of 50 from an untrusted location, scoring −0.88. These flagged anomalies can be further investigated to validate potential threats, providing actionable insights for the Anomaly Detection Phase of the forensic workflow.
Upon completion of the model training, Azure ML Studio facilitates the deployment of the model as a real-time scoring endpoint. This endpoint can be integrated with Azure Sentinel to monitor login events continuously. New login events from Azure Sentinel are sent to the model for scoring, and alerts for forensic teams are triggered by events identified as abnormal.
Events are continuously scored in real time, facilitating forensic analysts’ quick identification and response to potential compromises, such as unauthorized access attempts. This integration streamlines the forensic workflow, enabling proactive threat detection to be conducted in an automated and scalable manner.
Example Code for Deploying the Model in Azure ML Studio:
The deployment code first establishes a connection to an Azure Machine Learning workspace, which enables access to the machine learning environment necessary for managing and deploying models. The trained Isolation Forest model is registered within the workspace and deployed as a real-time scoring service utilizing an Azure Container Instance (ACI). The deployment comprises a script designated as score.py, within which the inference logic determines the scoring of incoming login events by the model. Upon deployment, a unique scoring URI is assigned to the service. The model is called in real time by Azure Sentinel through this URI, with new login events being sent to the deployed service for immediate scoring and anomaly detection.
7.2.4. Leveraging Machine Learning Models from Azure ML Studio to Enhance Azure Sentinel
Integrating machine learning models from Azure Machine Learning (Azure ML) Studio into Azure Sentinel significantly enhances the capabilities of Azure Sentinel’s forensic and threat detection processes. Azure Sentinel applies advanced, custom-built models trained on historical data to identify anomalies, detect subtle patterns, and respond proactively to emerging threats more accurately than rule-based systems. In this integration, the analytical backbone is provided by Azure ML Studio. At the same time, the operational layer is constituted by Azure Sentinel, which applies the model’s insights to real-time security events.
The native detection capabilities of Azure Sentinel are primarily based on predefined rules and anomaly detection models that emphasize common indicators of compromise. However, custom models developed in Azure ML Studio allow for tailoring detection algorithms to unique environments, resulting in models that exhibit increased sensitivity to specific behaviors or nuanced attack patterns. Low-frequency but high-impact anomalies, such as abnormal login times, atypical access locations, or unusual resource access patterns, are detectable by these models, which often signify advanced persistent threats or insider activity. Through this integration, Azure Sentinel can leverage machine learning to process large volumes of incoming security events, with only the most relevant threats being flagged for immediate investigation.
Upon training and deploying the machine learning model as a real-time scoring endpoint in Azure ML Studio, Azure Sentinel can utilize the model to score new security events continuously. The likelihood of abnormal login attempts can be evaluated through the model’s scoring. Sentinel’s alerting mechanism can prioritize high-risk events based on the model’s scoring, ensuring that security teams focus on incidents with the highest probability of compromise.
Azure Sentinel collects real-time login and activity logs from multiple sources, including Azure AD, Microsoft 365, and on-premises AD logs. The data are routed to the deployed model in Azure ML Studio. The scoring of each event is conducted by the model, utilizing features including login hour, login frequency, and location category. Events are assigned an anomaly score, with higher scores indicative of greater risk. When the anomaly score surpasses a predefined threshold, an alert is raised by Azure Sentinel, which provides security teams with contextual information regarding the flagged event and its corresponding anomaly score.
The following sample code is presented to illustrate the utilization of Azure Logic Apps for calling the deployed model in Azure ML Studio and processing the scoring results in Azure Sentinel:
A login event is retrieved from Azure Sentinel through its REST API at the beginning of the workflow. Essential fields such as UserPrincipalName, LoginHour, LoginFrequency, and LocationCategory are included in this event, serving as inputs for the machine learning model. Upon data extraction, they are transmitted to the deployed model endpoint in Azure ML Studio, where the model computes an AnomalyScore. The likelihood that the login event is suspicious is represented by this score, with higher scores indicating a greater probability of abnormal behavior. When the AnomalyScore exceeds a predefined threshold of 0.7, the workflow triggers a high-risk alert in Azure Sentinel. Contextual information from the model’s output is incorporated into this alert, enabling a focused and informed investigation into the flagged event by the security team:
For instance, a login was performed by
[email protected] at 3 a.m. with a high frequency from an untrusted location, which resulted in an anomaly score of 0.85 and triggered a “High-Risk Login Detected” alert. A highly suspicious pattern was exhibited by
[email protected], with an anomaly score of 0.92. The automated process is designed to enhance real-time anomaly detection, with the Incident Response Phase being streamlined by providing actionable alerts based on advanced machine learning analysis, enabling security teams to address threats more efficiently.
The integration of real-time scoring from Azure ML Studio into Azure Sentinel is associated with several advantages in the forensic investigation workflow:
Enhanced detection accuracy is achieved using a custom-trained machine learning model, which allows for identifying nuanced patterns that are challenging to capture using traditional rule-based methods. False positives are reduced, allowing for a focus on events that represent genuine threats by analysts.
The capability for real-time scoring facilitates the immediate analysis of incoming events, generating alerts for the security team within moments of an abnormal event. The time available for an attacker to exploit compromised accounts or escalate privileges within the system is minimized.
The manual workload is reduced by implementing automated scoring and alert generation, which streamline the detection process and diminish the necessity for manual analysis of each event. By automating routine evaluations, forensic teams may allocate resources to more complex investigations, improving overall efficiency.
Integrating Azure Machine Learning Studio models with Azure Sentinel enables forensic teams to proactively respond to complex cyber threats. Combining data transformation from Azure Data Factory with custom machine learning models in Azure ML Studio enhances Azure Sentinel’s ability to detect advanced threats, including abnormal login behaviors and atypical access patterns. The integration is associated with improvements in detection accuracy and timeliness, and a scalable, adaptive forensic workflow that can evolve alongside an organization’s security needs is established.
7.2.5. Benefits of Machine Learning and Artificial Intelligence in Azure Security Center
Integrating machine learning and artificial intelligence within Azure Security Center is a powerful enhancement to traditional security approaches. The detection, analysis, and response to threats by Azure Security Center are enhanced by the capabilities of ML and AI, resulting in greater speed, accuracy, and adaptability compared to rule-based systems alone. The transformation of Azure Security Center into a proactive security solution is achieved by applying advanced techniques that enable continuous learning from data, adaptation to evolving threats, and reductions in the burden on human analysts. The primary benefits of leveraging ML and AI in Azure Security Center are outlined below.
The ability of ML and AI to improve the accuracy of threat detection is considered one of the most significant benefits. Traditional security methods, including signature-based detection and static rule sets, often need help to detect new or evolving threats that do not conform to predefined patterns. In contrast, ML models trained on historical data can establish a baseline of normal behavior for users, devices, and applications. These models utilize behavioral baselines to detect subtle deviations indicative of potential security incidents, including abnormal login patterns, unexpected access locations, and unusual data transfers. Anomalies that fall outside typical usage patterns are identified, resulting in a reduction in false positives by ML-driven detection, which aids security teams in focusing on high-priority threats.
The capabilities of AI and ML facilitate the dynamic adaptation of Azure Security Center to new threats through continuous learning. As data are subject to change over time, the periodic retraining of the models within Azure ML Studio on fresh data is facilitated, allowing for the refinement of detection capabilities and the maintenance of effectiveness against emerging threats. For example, it has been observed that as user behaviors shift—whether due to seasonal variations, remote work trends, or organizational changes—baseline updates are made to ML models to accommodate these patterns. The likelihood of false alarms from legitimate changes is reduced through this adaptability while the system maintains vigilance to actual threats.
The responsiveness of Azure Security Center is significantly enhanced by integrating real-time anomaly detection. AI-powered models deployed in Azure ML Studio facilitate the immediate analysis of incoming security events, enabling the detection of and response to suspicious activity by Azure Security Center as it occurs. For instance, when a login event is observed to deviate from an established baseline in terms of time, location, or frequency, it is scored by the model as potentially abnormal. Azure Security Center raises an alert if the anomaly score surpasses a specified threshold, which enables instant notifications to be sent to security teams. This real-time analysis reduces the time for attackers to exploit vulnerabilities, and the response is accelerated, thereby mitigating potential damage.
In Azure Security Center, machine learning models provide a mechanism for automatically prioritizing threats based on risk scores. Anomaly scores are assigned to events, allowing incidents to be ranked based on their likelihood of being genuine security threats. The automated prioritization of alerts is designed to relieve security analysts from the manual review process, thereby enabling a concentration on high-severity threats and complex investigations. A login attempt characterized by a high anomaly score—suggesting a significant likelihood of compromise—would be assigned to a high-priority alert. In contrast, events assessed as lower risk would receive lower priorities. The efficiency and productivity of security teams are improved through reductions in false positives and the automatic ranking of alerts by ML and AI.
As organizations experience growth and their digital environments increase in complexity, it is observed that traditional security methods may encounter challenges in scaling effectively. The scalability of ML- and AI-driven solutions in Azure Security Center enables continuous monitoring across large, distributed, and hybrid environments. Vast volumes of data from multiple sources, including cloud resources, on-premises systems, and third-party integrations, are processed and analyzed by ML models. This capability ensures that all parts of an organization’s infrastructure are monitored uniformly, irrespective of scale. Furthermore, it has been demonstrated that automated ML workflows enable the maintenance of scalability within Azure Security Center while ensuring that the precision and timeliness of threat detection are not compromised.
Advanced persistent threats are frequently characterized by stealth and longevity, which results in challenges for detection using traditional rule-based approaches. ML models within Azure Security Center enhance the ability to identify sophisticated threats by uncovering subtle patterns and correlations that may not be immediately apparent. For example, low-frequency but high-risk activities, such as privilege escalations followed by unauthorized data access, may be involved in an APT. AI-powered models can correlate these events over time, linking seemingly benign activities into a coherent attack chain and alerting security teams before the attacker’s objective is achieved. The dwell time of threats within the environment is minimized through proactive detection, which reduces the potential for data breaches and operational disruption.
Integrating artificial intelligence and machine learning into Azure Sentinel is a transformative approach to forensic analysis in cloud environments, with proactive and adaptive responses to increasingly sophisticated cyber threats being enabled. The centralization of data from diverse sources and the application of machine learning for adaptive anomaly detection result in an enhanced ability to detect subtle and complex attack vectors that are often overlooked by traditional rule-based methods in Azure Sentinel. This case study is exemplified by how AI-driven forensics enables faster and more accurate detection, analysis, and response to incidents, with the platform’s potential to support robust security monitoring being showcased. Through a structured and adaptive forensic workflow, which incorporates advanced anomaly detection models in Azure Machine Learning Studio, the evolution of cybersecurity posture from reactive to proactive is facilitated for organizations. Azure Sentinel is positioned as a critical tool within this AI-enhanced framework for constructing resilient, scalable, and efficient defenses that address the unique challenges presented by today’s cloud-centric cyber landscape.