Suspicious Webshell Written To F5 TMUI Web Directory
- Product
- linux
- Category
- file_event
- Author
- HuntRule
- Published
- 2026-06-09
- Updated
- 2026-08-28
ATT&CK techniques
PersistenceRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects creation of a PHP or JSP file within the F5 BIG-IP xui web directory tree which is where operators dropped webshells after TMUI exploitation as described in NCC Group RIFT F5 TMUI intelligence. Adversaries plant these webshells to maintain persistent remote command execution on the appliance so any script file appearing in these image and script paths is highly suspicious.
Reporting behind it
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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