This detection rule identifies modifications to OpenSSH binaries, which can be indicative of adversarial activity aimed at persistent unauthorized access or credential theft. The rule monitors for file changes in key OpenSSH executables such as `scp`, `sftp`, `ssh`, and `sshd`, along with the library `libkeyutils.so`. Compromised OpenSSH tools can allow attackers to gain ongoing access or extract credentials for further exploitation. The detection mechanism is rooted in file event monitoring, specifically targeting Linux environments by analyzing logs for alterations in these sensitive components. False positives may arise from legitimate updates; therefore, it is critical to verify the integrity of any modifications. The investigation process includes assessing user activity correlated with changes and cross-referencing recent alerts to confirm legitimacy. Immediate actions require incident response protocols to isolate affected systems and potentially cleanse them of malware or backdoors. This approach not only addresses the immediate threats but also fortifies defenses against similar future incursions.