Suspicious Firewall Rule Added for Masqueraded csrss Process via netsh

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 netsh advfirewall creating a firewall rule referencing a csrss-named program. Bundled malware masquerades its payload as the system process csrss and allows it through the firewall to enable C2 traffic. Combining a system-process name with an attacker-created firewall rule is a strong evasion signal.

Reporting behind it

Related detections9 linkedT1686 — drag to rearrange

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Suspicious Firewall Rule Added for Masqueraded csrss Process via netsh

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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