huntrule

Sitecore Pre-Auth RCE (CVE-2021-42237) exploitation attempts via Report.ashx POST

Alerts on successful HTTP POST traffic targeting Sitecore Reporting Report.ashx associated with CVE-2021-42237.

FreeReviewedSigma · High · v5
Category
webserver
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2021-11-17
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Initial Access

  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. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags HTTP requests that return a 200 response where the request is a POST with a query containing /sitecore/shell/ClientBin/Reporting/Report.ashx. This matters because successful pre-auth RCE exploitation attempts against Sitecore could enable remote code execution without authentication. The detection relies on webserver HTTP telemetry including request method, URI query content, and HTTP status codes.

Reporting behind it

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Possible Ivanti Pulse Connect Secure Command Injection via License Keys-Status Endpoint (via webserver)
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Sitecore Pre-Auth RCE (CVE-2021-42237) exploitation attempts via Report.ashx POST
Pivot detection · T1190 · 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.