ComRAT Proxy HTTP Requesting index.php with h Parameter

Flags proxy HTTP requests with URIs containing /index/index.php?h=, consistent with web-based C2 behavior.

FreeReviewedSigma · High · v5
Category
proxy
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2020-05-26
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 identifies suspicious proxy web traffic with a URL path matching /index/index.php?h=. Such requests can indicate command-and-control style communications where an attacker embeds tasking or parameters in HTTP query strings. Detection relies on proxy telemetry that records the requested URI and flags when it contains the specified substring. The match is a narrow indicator of activity consistent with ComRAT network communication as described by the rule source.

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ComRAT Proxy HTTP Requesting index.php with h Parameter
Pivot detection · T1071.001 · 9 related

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. 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.