This detection rule identifies the creation of the `mimilsa.log` file, which is associated with the use of the Mimikatz tool's `memssp` module. Mimikatz is notorious for harvesting credentials from a compromised system, particularly during post-exploitation scenarios. The rule targets specific Windows log file creation events within timeframes of the last nine months, specifically looking for instances where this file is created with the `lsass.exe` process involved. The rule's investigation guidelines suggest several steps, such as analyzing process trees, checking for other alerts, and inspecting potential malicious DLLs in proximity to the log file. It also includes information on how to handle false positives, as this log file should not normally be created under legitimate circumstances, and it outlines various response and remediation strategies to mitigate the impact of a credential compromise effectively.