EX13-CA-000075 - Exchange must have Audit data protected against unauthorized modification.
Log files help establish a history of activities, and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. Audit log content must always be considered sensitive, and in need of protection. Audit data available for modification by a malicious user can be altered to conceal malicious activity. Audit data might also provide a means for the malicious user to plan unauthorized activities that exploit weaknesses. The contents of audit logs are protected against unauthorized access, modification, or deletion. Only authorized auditors and the audit functions should be granted Read and Write access to audit log data. NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.
Update the EDSP. Navigate to the location of the audit data. By default, the logs are located on the application partition in \Program Files\Microsoft\Exchange Server\V15\Logging Restrict any unauthorized groups' or users' modify permissions for the audit logs.