Malicious BRICKSTORM C2 over WebSocket to Cloudflare Workers Domain (via proxy)
- Category
- proxy
- Author
- HuntRule
- Published
- 2026-10-13
- Updated
- 2026-10-13
ATT&CK techniques
C2Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
Exfiltration
Impact
What it detects
This rule detects WebSocket connections to a workers.dev subdomain used by the BRICKSTORM backdoor for command-and-control. Following Ivanti exploitation the actor tunneled BRICKSTORM traffic through Cloudflare Workers infrastructure to reach compromised vCenter hosts. Outbound wss traffic to attacker-registered workers.dev endpoints is a distinctive C2 indicator.
Reporting behind it
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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