Modification of OpenSSH Binariesedit
Adversaries may modify SSH related binaries for persistence or credential access by patching sensitive functions to enable unauthorized access or by logging SSH credentials for exfiltration.
Rule type: query
Rule indices:
- auditbeat-*
- logs-endpoint.events.*
Severity: medium
Risk score: 47
Runs every: 5 minutes
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Linux
- Threat Detection
- Credential Access
- Persistence
Version: 100 (version history)
Added (Elastic Stack release): 7.12.0
Last modified (Elastic Stack release): 8.5.0
Rule authors: Elastic
Rule license: Elastic License v2
Potential false positivesedit
Trusted OpenSSH executable updates. It’s recommended to verify the integrity of OpenSSH binary changes.
Rule queryedit
event.category:file and event.type:change and process.name:* and
(file.path:(/usr/sbin/sshd or /usr/bin/ssh or /usr/bin/sftp or
/usr/bin/scp) or file.name:libkeyutils.so) and not
process.name:("dpkg" or "yum" or "dnf" or "dnf-automatic")
Threat mappingedit
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
-
Technique:
- Name: Create or Modify System Process
- ID: T1543
- Reference URL: https://attack.mitre.org/techniques/T1543/
-
Tactic:
- Name: Credential Access
- ID: TA0006
- Reference URL: https://attack.mitre.org/tactics/TA0006/
-
Technique:
- Name: Modify Authentication Process
- ID: T1556
- Reference URL: https://attack.mitre.org/techniques/T1556/
Rule version historyedit
- Version 100 (8.5.0 release)
-
- Formatting only
- Version 3 (8.4.0 release)
-
-
Updated query, changed from:
event.category:file and event.type:change and process.name:* and (file.path:(/usr/sbin/sshd or /usr/bin/ssh or /usr/bin/sftp or /usr/bin/scp) or file.name:libkeyutils.so) and not process.executable:/usr/bin/dpkg
-