Suspicious Firewall Allow Rule for TightVNC Server via netsh (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 BlotchyQuasar adding a Windows firewall allow rule for its TightVNC tvnserver.exe binary staged under AppData to permit inbound remote-control traffic. Creating a firewall exception for a VNC server running from a user profile is anomalous. This exposes the host to covert remote access.

Reporting behind it

Related detections9 linkedT1686 — drag to rearrange

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Suspicious Disabling or Flushing of the Linux Host Firewall (via process_creation)

Malicious Firewall Deactivation - PowerShell (via powershell)

Malicious Firewall Deactivation - Firewall (via firewall-as)

Suspicious Firewall Allow Rule for TightVNC Server via netsh (via process_creation)

Pivot detection · T1686 · 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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