Masquerading
Where this stands
No Sigma rule can address this — the telemetry MITRE names has no Sigma logsource behind it.
Sigma has no logsource taxonomy for ICS. MITRE's telemetry here is operational historians and controller state, which no Sigma rule can address.
What the technique is
Adversaries may use masquerading to disguise a malicious application or executable as another file, to avoid operator and engineer suspicion. Possible disguises of these masquerading files can include commonly found programs, expected vendor executables and configuration files, and other commonplace application and naming conventions. By impersonating expected and vendor-relevant files and applications, operators and engineers may not notice the presence of the underlying malicious content and possibly end up running those masquerading as legitimate functions. Applications and other files commonly found on Windows systems or in engineering workstations have been impersonated before. This can be as simple as renaming a file to effectively disguise it in the ICS environment.
Read it on attack.mitre.orgWhat MITRE says you would watch
- AN1858
Monitor for newly constructed services/daemons that may attempt to manipulate features of their artifacts to make them appear legitimate or benign to users and/or security tools. Monitor for changes made to files outside of an update or patch that may attempt to manipulate features of their artifacts to make them appear legitimate or benign to users and/or security tools. Monitor for file names that are mismatched between the file name on disk and that of the binary's metadata. This is a likely indicator that a binary was renamed after it was compiled. For added context on adversary procedures and background see Masquerading and applicable sub-techniques. […]
Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.