Suspicious Crypto Miner User Agents in Proxy Logs

Flags proxy requests with User-Agent prefixes tied to XMRig or CCMiner crypto miners.

FreeReviewedSigma · High · v2
Category
proxy
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2019-10-21
Updated
2026-07-31

ATT&CK techniques

C2
  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. Exfiltration

  13. Impact

What it detects

This rule flags proxy log events where the client user agent begins with known crypto miner identifiers ("XMRig " or "ccminer"). Attackers and bot operators often use miners with distinct user agents, so matching these strings helps identify potential unauthorized mining activity. Detection relies on proxy telemetry that records HTTP user agent values for incoming requests.

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Suspicious Crypto Miner User Agents in Proxy Logs
Pivot detection · T1071.001 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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