Suspicious PHP Webshell in Netscaler VPN Theme Directory

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 PHP files under the Netscaler /vpn/themes/ path, where the actor planted webshells following Netscaler exploitation. The theme image directories serve static assets and should not host PHP, so PHP execution there indicates a webshell used for post-exploitation access.

Reporting behind it

Related detections9 linkedT1505.003 — drag to rearrange

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Suspicious PHP Webshell in Netscaler VPN Theme Directory

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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