Possible Citrix NetScaler Webshell Access in VPN Theme Path (via webserver)

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects requests to a php file inside the Citrix NetScaler vpn theme path which is used to interact with the webshell dropped during CVE-2026-8452 exploitation. The theme path normally serves only static template assets, not php.

Reporting behind it

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Possible Citrix NetScaler Webshell Access in VPN Theme Path (via webserver)

Pivot detection · T1505.003 · 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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