Possible Citrix NetScaler CVE-2023-4966 Session Token Disclosure

ATT&CK techniques

Initial Access → Cred Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1539Steal Web Session Cookie
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects HTTP requests to the OpenID configuration discovery endpoints on Citrix NetScaler that are abused by CVE-2023-4966 to disclose session memory and steal valid session tokens. When paired with an abnormally large Host header these requests indicate exploitation attempts against an exposed NetScaler appliance for session hijacking.

Reporting behind it

Related detections9 linkedT1190 — drag to rearrange

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Possible Citrix NetScaler CVE-2023-4966 Session Token Disclosure

Pivot detection · T1190 · 9 related

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

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