Possible SonicWall Credential Testing via userLogin Endpoint

ATT&CK techniques

Initial Access → Cred Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1110Brute Force
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects HTTP POST requests to the SonicWall /cgi-bin/userLogin endpoint, the interface used by NetExtender and web login for credential submission. In the observed campaign this endpoint is hit through commercial proxy infrastructure to test credentials against internet-facing SonicWall firewalls. A high rate of such POST requests indicates brute-force or credential-stuffing activity against the SSL-VPN login surface.

Reporting behind it

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Possible SonicWall Credential Testing via userLogin Endpoint

Pivot detection · T1190 · 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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