4738 - Account Changed

https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4738

Event ID 4738 in the Windows Security Event Log signifies a user account was changed. This event is critical within the audit category of "User Account Management" and is logged whenever attributes of a user account are modified. These modifications can include changes to the account's name, description, password, group membership, and other attributes. Monitoring Event ID 4738 is essential for security professionals to track changes to user accounts, which can indicate routine maintenance or potentially unauthorized or malicious modifications aiming to escalate privileges or expand access within a system.

Logged by the Security subsystem in Windows when changes are made to a user account's properties.

Category: Audit User Account Management

Significance:

• Security Implications: Unauthorized modifications to user accounts, such as elevating privileges, adding users to privileged groups, or changing account properties to evade auditing or restrictions, are common tactics used by attackers. Event ID 4738 helps in identifying such changes.

• Operational Integrity and Compliance: Ensuring that user account changes are documented and authorized is crucial for maintaining operational security and compliance with regulatory and organizational policies.

Details Included in Event ID 4738

• Subject: The account that performed the change, including Security ID, Account Name, Domain Name, and Logon ID.

• Target Account: Details about the account that was changed, such as Security ID and Account Name.

• Changed Attributes: Lists the specific attributes that were modified. This can include:

  • User account name

  • Display name

  • User principal name (UPN)

  • Home directory

  • Home drive

  • Script path

  • Profile path

  • User workstations

  • Password last set

  • Account expiration date

  • Primary group ID

  • Allowed/Denied logon hours

  • Account options (e.g., password never expires, user cannot change password, etc.)

  • Additional information like group memberships may also be noted.

How to Use Event ID 4738 for Security

Monitoring for Unauthorized Changes: Configuring alerts based on this event ID can aid in the early detection of unauthorized account modifications, potentially indicating an internal threat or a compromised account.

Forensic Analysis: In the aftermath of a security incident, analyzing Event ID 4738 entries can help reconstruct the sequence of events, especially to identify how attackers might have modified account properties to facilitate their activities.

Policy and Compliance Audits: Regular reviews of account changes logged by Event ID 4738 are vital for verifying compliance with access control policies and regulatory requirements, ensuring that only authorized modifications are made to user accounts.

Best Practices for Monitoring Event ID 4738

• Enable Comprehensive Auditing: Ensure that "Audit User Account Management" is enabled through Group Policy to capture events related to user account modifications.

• Regular Reviews and Audits: Incorporate the examination of Event ID 4738 into routine security audits to identify and rectify unauthorized or suspicious account modifications.

• Correlate with Other Events: Analyze Event ID 4738 in conjunction with other security events (such as Event IDs 4720, 4722, 4728, etc.) to gain a fuller understanding of account lifecycle activities and potential security implications.

• Utilize SIEM Tools: Employ Security Information and Event Management (SIEM) solutions to aggregate, correlate, and analyze Event ID 4738 alongside other security events for comprehensive monitoring and alerting on suspicious activities.

Limitations

Event ID 4738, while informative, does not inherently indicate malicious intent; changes to user accounts can be routine or necessary for business operations. It requires contextual analysis and correlation with other indicators of compromise or unauthorized activities to accurately identify malicious actions.