Hybrid identity environments combining on-premises Active Directory (AD) with Microsoft’s cloud-based Entra ID (formerly Azure AD) are now standard for most organizations. Their logs come from vastly different architectures, an on-premises hierarchical database and a cloud-based identity service, which creates serious correlation challenges due to schema, format, and time discrepancies.
When logs are not correlated between systems, it’s almost impossible to compare timestamps, user activities, and events across them. Getting a comprehensive picture of your security posture is impossible.
When You Actually Need AD + Entra Log Correlation
If you correlate logs from both your on-premises Active Directory and Entra ID, you will be able to identify hybrid threats that each of the two tools on their own wouldn’t be able to detect. Here are some high-impact scenarios where this kind of hybrid visibility is necessary:
- Account Created On Premises: A new user account is generated in on-premises Active Directory during a privileged account escalation. Azure AD Connect instantly grants it a privileged role by syncing it with a synced group that is role-assignable or linked to Entra ID administrative privileges. In the absence of correlation, the Entra privilege elevation would be undetected and the creation on the on-premise side would be viewed as a harmless event
- Conditional Access Evasion: In a legacy Active Directory scenario, a malicious actor includes the victim in a security group which gets synced via Azure AD Connect to an Entra ID group used in conditional access policies. Because of the delay in synchronization between the local AD and Entra ID, the victim can circumvent MFA or location verification before the modification is completely propagated. As the logs continue to be segregated between the on premises and cloud environments, this “valid” group membership change goes unnoticed by the cloud security teams.
- Sign-In to Lateral Movement: A suspicious Entra ID sign-in from a risky IP/location was observed, followed by the discovery that synced credentials enabled the initial lateral movement in on-premises Active Directory via Kerberos. If you correlate the two, you will find out the cloud entry is the first step in the attack, not just a failed login attempt.
- Service Account Misuse: A compromised Active Directory (AD) service account, configured with a Service Principal Name (SPN), is allowed to authenticate an Entra ID workload through the Microsoft Graph API. This opens the path for the attacker to turn around and access on-premises file shares and SQL databases. Such cross workloads patterns can clearly reveal hidden persistence that single domain monitoring will never see.
Understanding the Data Sources
1. On-Premises Active Directory Logs
AD logs reveal user actions, group changes, logons, external threats, missed cloud activity, and normalized identities across hybrid environments. Some key security event log IDs to monitor would include:
| Event ID | Description |
|---|---|
| 4624 | For successful logons (with workstation names) |
| 4647/4648 | For logoff sessions |
| 4672 | For privileges granted |
| 4728/4732/4756 | For group membership |
| 4768/4769 | For Kerberos auth ticket operations |
Latency averages seconds to 5 minutes via agents/SIEM forwarding, though DC queues can hit 30 minutes in overload. Retention defaults to 7-90 days (configurable), requiring external SIEM post-overflow.
2. Microsoft Entra ID Logs
Audit logs detail changes in admin-initiated actions such as role assignments, policy changes and the initiator and the target whereas sign-in logs reveal the auth attempts thoroughly including the MFA status, client apps used, and conditional access outcomes.
- Difference in Identity Representations– UPN is used to authenticate users in hybrid scenarios but can change in case of mergers. Object ID is Azure’s permanent and unique cloud identity. The on – premises object GUID will never correspond to the object ID, so correlation is done by Azure AD Connect sync attributes such as ms-DS-ConsistencyGuid as sourceAnchor, thus breaking the naive SID based lookups.
- Cloud-Only Context– The cloud only context where you won’t get on-premises for instance – risk detections mark impossible travel scenarios leaked credential alerts via Dark Web monitoring. Records app consents, conditional access blocks (IP, restricted logins), SaaS patterns (unusual Box downloads), global sign- ins lack visibility of domain controllers.
The Core Correlation Challenges
The following are the main correlation issues that cause security teams issues:
- Identity Mismatches: AD uses SID/objectGUID, Entra uses Object ID (UUID) and UPN. The same user appears differently across platforms. Correlation relies on Azure AD Connect attributes like ms-DS-ConsistencyGuid as sourceAnchor. Due to this mismatch, events like logons and privilege escalations cannot be automatically linked with normalization tools, and the analysts therefore waste hours manually mapping identities.
- Time-Skew and Log Latency: The phenomenon known as “time-skew” occurs when a signal, usually a clock, reaches various components at various times. Logs require time to spread from endpoints to SIEMs, and server clocks fluctuate by seconds or minutes. Timeline-based correlation is lost if a privilege change is recorded somewhere else. Although latency allowance and NTP syncing are essential, they are often disregarded.
- Partial Visibility: Directory sync tools capture changes, but they do not record live activities such as session hijacking or just-in-time access. The information gets leaked “user synced” but not what the user did after the sync, which opens the blind spots for attack chains. The full visibility is possible only with agent- based logging that goes beyond sync alone.
- Volume and Noise:Environments produce millions of events each day; benign noise (e. g. , routine authentications) masks anomalies such as lateral movement. Filtering exhausts simple tools, which pushes teams to manually tune rules. AI driven baselining is helpful, but the setup is complicated.
- Manual Correlation Fatigue: Analysts piece together events from logs using spreadsheets or queries, and they must repeat this for every incident. This method does not scale, thus leading to analyst burnout and consequently missed threats in role management risks. Automation using UEBA platforms helps in reducing the fatigue but requires integration at the outset.
Prerequisites Before You Attempt Correlation
Here are the prerequisites before attempting correlation:
- Time Synchronization: Event correlation across on premises domain controllers(DCs) and cloud services such as Azure AD/Entra ID requires accurate timestamps. A time difference between the clocks can lead to false negatives during the sequence of analysis of events such as failed logon events being considered as unrelated to privilege escalations. All systems should be synchronized using NTP servers or Azure Time sync before starting to work.
- Log Retention and Access: Storing logs for a long time helps capture the entire timeline of the attack while having them readily available can be a lifesaver during a crisis. Lack of retention time makes the forensic process incomplete. Make sure that the Event Viewer on DCs, Azure Monitor logs, and Microsoft Sentinel tables should be easily accessible for investigators via RBAC permissions such as Security Reader roles. To avoid delays during incidents, logs should be readily available for immediate use. Insufficient log retention can result in incomplete forensics investigations.
- Clear Investigations Scope:Unclear scopes lead to waste of resources. The proper way is to formulate some hypothesis like show that unauthorized admin gave access via this SID or find out if sign in failures correlate with brute force attempts. This way noise is filtered, relevant logs are prioritized and actional insights are delivered, thus avoiding the situation of an extensive ingestion without any conclusions.
How to Correlate Windows AD and Entra ID Logs
Below are the steps for how to correlate on-prem AD and Entra ID logs:
- Identify the Identity: Initially, locate the specific user or service account that is at the center of your investigation. When dealing with AD logs, look up the SAM AccountName or SID for reference, for Entra ID use UPN (User Principal Name) or Object ID from audit/ sign, in logs. This would ensure to follow the same entity even in hybrid environments and not get mismatched due to sync delays.
- Normalize Identifiers: Use Entra Connect attribute mappings or custom expressions to standardize attributes such as UPN, employee ID, or object GUID. While AD can use on premises naming conventions. Entra adds domains and unify them through sync rules to perform accurate joins. This step prevents false negatives in correlations due to format discrepancies.
- Align Timelines: Convert all timestamps into UTC and use correlation IDs as it relies on identity attributes, time windows, behavioral sequencing. Take into consideration the sync latency by allowing time windows in your queries. Correct alignment can disclose the relationship of cause and effect such as Active Directory auth resulting in Entra access.
- Trace Lifecycle Events: Identify the complete sequence that starts with creation (AD 4720/ 4738 for lifecycle events, authentication (4624 Entra sign-in), and privilege changes (4672 for Special privileges assigned to new logon). For continuity utilize synchronized metadata. This procedure guided path reveals the use of persistence or lateral movement.
- Validate Intent vs Anomaly: Establish a baseline of regular patterns (like usual login patterns) against logs with the help of statistical thresholds or UEBA rules. Mark deviations such as rare privilege escalations or cross tenant access. Verify the risk indicators in Entra ID Protection to confirm the intent.
The Manual Approach
Export Logs: Obtaining request, separate Windows AD logs by Event Viewer, PowerShell, or forwarding method to SIEM. Entra data running via Azure portal, Graph API, or exporting to Log Analytics Workspace. The retention is 7 days (Free) and 30 days (P1/P2) for Entra ID sign-in & audit logs. Combine in tools like Excel or Splunk for initial pivots.
Query in SIEM: Perform KQL queries in Sentinel (e. g. ADLog | join EntraLog on UPN or SPL in Splunk for joins on normalized fields. Filter by risk events like failed auths. Review results in timelines to spot sequences manually.
Visualize/Review: Map events over time in visualization tools such as Power BI, use color coding to show anomalies. Preparing documentation of your findings with screenshots that would help for audits. The last would be to refine queries with new data based on first impressions.
The Automated Approach
Native SIEM Rules: Configure Sentinel analytics rules for agent, assisted auto, ingestion, and cross-log correlations based on Entra Connect Health data. The system initiates lifecycle anomaly notifications, like a rogue admin added.
Third Party Platforms: After obtaining the data via APIs, programs like ManageEngine Log360 and Elastic use machine learning (ML) to execute automated playbooks and identify anomalies in real time. Custom algorithms that attempt to manage differences in schemas function well.
Lifecycle Workflows: For automatic reviews (like offboarding), Entra’s native workflows generate triggers from AD sync events; Logic Apps are used for integration in custom tracing scenarios.
Common Mistakes to Avoid When Correlating AD and Entra ID Logs
The key major mistakes to avoid while correlating AD and Entra ID logs are listed below:
- Treating Sync Events as User Actions: Directory changes from on-premises AD to Entra ID are reflected in Entra ID Connect sync events; however, these changes are entirely automatic and are not started by users. False positives are produced when they are mistakenly identified as malicious activity, and the effort spent investigating a benign directory synchronization is squandered. To concentrate on actual risks, always filter sync, related event IDs, and cross-reference with sync schedules.
- Assuming Entra Logs Replace AD Auditing: For cloud sign-ins and app access, Entra ID logs are quite great, but they totally ignore on-premises AD alterations like GPO changes or schema updates. You are essentially ignoring all those hybrid attack pathways that use the outdated environments for their double act if you do not have native AD auditing via Event Viewer or with the help of tools like Lepide. For a combined visibility across the environments, activate the advanced auditing policies on your domain controllers and connect them to your SIEM.
- Correlating Without Business Context: Without taking into account IT process, raw event correlation (such as failed logons + admin logon) detects a typical helpdesk password reset as a security assault. The security team will become confused and take longer to respond to the actual issue as a result, and alert volumes. To provide business context and risk prioritization linked to business effect, use asset inventories, role-based baselines, and stakeholder feedback
- Evaluating Alerts Rather than Behaviors: Alerts only record one occurrence, such as a dangerous sign, but the attacker can avoid point-in-time detection by carrying out several activities over several days. Choose UEBA (User and Entity Behavior Analytics) solutions, which learn the typical behavior of users and entities and then detect deviations, such as a new administrator accessing a new IP address at an unusual time.
Best Practices for Ongoing Hybrid Identity Visibility
Below are the strategies that embed visibility into daily workflows, reducing breach windows by correlating data continuously and quantifying real business stakes.
- Shift to Continuous Correlation: Monitoring is reactive and only records incidents. However, a higher level of security necessitates the use of tools like SIEM or Lepide to aggregate logs from cloud apps, identity providers like AD, and Entra ID into a single stream. In order to spot anomalies like privilege creep among tenants or service principals that are no longer required, correlations can then be performed hourly. By using this method, MTTD is greatly decreased from days to minutes without requiring manual examination.
- Identity Hygiene as a Prerequisite: Neglect of identity hygiene stale accounts, over permissioned groups is responsible for AD attacks. Therefore, keep it as a minimum standard that needs to be maintained with automated PowerShell scripts running on a schedule or platform dashboards. Weekly scans flag inactive users, redundant roles, and unused SIDs. Before proceeding with advanced monitoring, a clean and secure attack surface must be ensured to provide it with a solid ground rather than quicksand.
- Alerts on Patterns, Not Single Events: A single login or role change is just a noise, maturity adjusts alerts for sequences such as three failed authentications from a new Azure region followed by admin elevation. Use machine learning baselines in your SIEM to baseline normal behaviour per user per role., triggering only when deviations exceed. This eliminates false positives, allowing SOC to focus on threats that are orchestrated like persistence or lateral movement.
- Mapping Identity Risk to Business Impact: Without taking context into account, generic risk ratings use CMDB integration to link identities to assets and then simulate the blast radius. Impact multipliers for revenue ties or compliance (GDPR fines) might be allocated for dashboard prioritization. This maturity metric results in management approval, so security is now viewed as a business protection rather than a cost.
Conclusion
Fragmented logs are a source of blind spots as various events stay separated, hiding hybrid threats while investigators manually piece the data together. Correlation unifies visibility, combining AD/Entra/Microsoft 365 logs into strings and patterns that reveal attack paths in a flash.
What Teams Gain When Correlation is Done Right:
- Faster Threat Hunting: A comprehensive contextual intelligence pool obtained by correlating various identity sources can reduce the investigation time thus, enabling rapid response to active threats.
- Reduced MTTR: Automation of anomaly detection with the help of built- in correlation rules can reduce mean time to respond from hours to minutes.
- Proactive Risk Mitigation: Constant surveillance recognizes privilege creep as well as over-provisioning issues that are resolved before attackers take advantage of them.
Why Hybrid Identity Visibility is Foundational to Zero Trust:
- Verifies Every Access: Continuous validation across cloud and on premises guarantees that no implicit trust exists between environments.
- Enforces Least Privilege: Dynamic policy enforcement disallows standing privileges in multi, cloud, multi, domain architectures.
- Builds Trust through Monitoring: Real-time behavioural analytics substitute static perimeter defense with identity, centric security.
Lepide connects Entra ID and On-Premises Active Directory by combining their audit logs into a single, unified picture. This combined approach highlights hybrid threats that distinct tools are unable to identify, including cross-environment privilege escalations.
By providing actionable context, intelligent alerts and real-time insights, Lepide enables proactive defense, compliance, and prompt threat response throughout your identity environment.
Ready for unified AD and Entra ID logging? Schedule a demo with our engineers or start your free trial today.
