huntrule

SolarWinds Orion Web API auth bypass probing via suspicious WebResource requests

Detects likely SolarWinds Orion API authentication bypass probing by matching suspicious WebResource/i18n endpoint query strings while filtering known valid requests.

FreeReviewedSigma · Critical · v5
Category
webserver
Author
Bhabesh Raj, Tim Shelton (SigmaHQ), DRL 1.1
Published
2020-12-27
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 whose URI query contains specific ASP.NET handler and i18n paths commonly associated with SolarWinds Orion API bypass attempts. Attackers may use crafted Orion endpoints to evade authentication and interact with internal functionality. The detection relies on webserver request telemetry, matching on `cs-uri-query` substrings for the targeted handler paths and the presence of SolarWinds API-related URI segments, while excluding known valid request patterns.

Reporting behind it

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SolarWinds Orion Web API auth bypass probing via suspicious WebResource requests
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.