huntrule

Citrix ADC/ADS Exploitation Attempts Targeting RAPI and PCIDSS Paths (CVE-2020-8193/8195)

Flags Citrix ADC/NetScaler HTTP requests whose URI queries match exploitation-related patterns for CVE-2020-8193 and CVE-2020-8195.

FreeReviewedSigma · Critical · v5
Category
webserver
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2020-07-10
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 webserver requests whose query strings match specific Citrix ADC/ADS exploitation patterns associated with CVE-2020-8193 and CVE-2020-8195. The behavior matters because attackers may use crafted application-layer requests to trigger vulnerable code paths for unauthorized access or payload delivery. Detection relies on HTTP webserver telemetry, specifically the presence of targeted substrings within the request URI query parameters.

Reporting behind it

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Cisco IOS XE Configuration Change by Web UI WSMA User
Possible React2Shell CVE-2025-55182 Prototype Pollution Exploitation
Citrix ADC/ADS Exploitation Attempts Targeting RAPI and PCIDSS Paths (CVE-2020-8193/8195)
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.