Malicious Koske DNS Configuration Locking via chattr (via process_creation)

ATT&CK techniques

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

What it detects

This rule detects the Koske malware hardening its hijacked DNS configuration by overwriting /etc/resolv.conf with attacker chosen resolvers and then setting the immutable attribute with chattr. Locking resolv.conf prevents defenders and legitimate services from restoring name resolution. This behavior is rare on production Linux hosts.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Malicious Koske DNS Configuration Locking via chattr (via process_creation)

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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