Suspicious Clearing of hosts.deny Access Restrictions on Linux

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1070Indicator Removal
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects shell activity that clears or overwrites the etc hosts.deny file. Automated SSH intrusion actors wipe host based access controls immediately after login to guarantee continued reachability before injecting their own authorized keys.

Reporting behind it

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Suspicious Clearing of hosts.deny Access Restrictions on Linux

Pivot detection · T1685 · 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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