The rule "Abnormal Process ID or Lock File Created" targets the creation of process ID (PID), lock, or reboot files in the Linux directory /var/run. On Linux systems, PID files serve to maintain process states and can be manipulated by malware to disguise executable files as legitimate PID files. Malicious actors may create these files to support various nefarious activities, including misrepresenting malware operations as normal system behavior. The rule uses a KQL query to identify events in the logs of the endpoint, focusing on file creations related to PID files and filtering out known benign processes. Analysts are provided with investigation guidance to assess the validity of any flagged files, including checks on file contents, types, size, and entropy, and they should trace any detected files back to their source process. False positives occur when legitimate PID files are detected, but these can be mitigated by checking specific file characteristics. The overall risk score assigned to this rule is 47, indicating a medium level of concern regarding potential threats. The rule emphasizes the need for a thorough incident response protocol, including isolating affected systems, credential reviews, and malware scans while maintaining logging and response strategies to enhance detection and response times.