Suspicious CurKeep Backdoor C2 API Endpoints (via proxy)

PremiumReviewedSigma · Low · v1
Category
proxy
Author
HuntRule
Published
2026-07-09
Updated
2026-08-28

ATT&CK techniques

C2 → Exfiltration
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. Impact

What it detects

This rule detects web requests to the shell and file API endpoints used by the CurKeep backdoor for command-and-control in the Stayin Alive campaign. The fixed api shell and api file URI paths reflect the backdoor tasking channel and help surface implant traffic in proxy logs.

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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.