Suspicious Clearing of Linux Authentication and History Logs

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1070.003Clear Command History
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects removal or truncation of Linux authentication and shell history artifacts such as auth.log wtmp btmp and bash_history which the Salt Typhoon intrusions performed to erase evidence of access on compromised network devices and hosts. Deleting or emptying these files is a strong indicator of anti forensic activity following unauthorized access.

Reporting behind it

Related detections9 linkedT1685.006 — drag to rearrange

Suspicious Shell History Clearing or Disabling (via process_creation)

Suspicious Deletion of System Logs Under var log on Linux Appliance

Suspicious COLDRIVER RunMRU History Clearing via Reg Delete (via process_creation)

Suspicious Clearing of System Logs on Linux (via process_creation)

Suspicious File Immutability Set via chattr for Anti-Removal on Linux

Malicious Sed Tampering of Juniper Syslog Configuration by UNC3886 (via process_creation)

Suspicious Linux Log Sanitization via sed In-Place Edit

Suspicious utmpdump Usage for wtmp Log Manipulation

Windows Registry RunMRU Key Deletion

Suspicious Clearing of Linux Authentication and History Logs

Pivot detection · T1685.006 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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