Suspicious Hosts File Modification to Block Security Vendors via file_event

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 writes to the Windows hosts file at drivers\etc\hosts. The Dragon Boss PUP edited this file to null-route antivirus and security vendor domains so protection tools could not update or communicate, so unexpected modification of the hosts file indicates an attempt to sever endpoint defenses.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Malicious Whole-Drive Defender Exclusion via Add-MpPreference (via ps_script)

Suspicious Disabling of WinRM Service via sc config

Suspicious Service binPath Hijack Followed by System Reboot

Suspicious Hosts File Modification to Block Security Vendors via file_event

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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