Malicious WordPress Webshell session-manager PHP in mu-plugins
- Product
- linux
- Category
- file_event
- Author
- HuntRule
- Published
- 2026-08-15
- 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 session-manager.php file inside the WordPress must use plugins directory. ErrTraffic deploys this file as a persistent server side backdoor on compromised WordPress installations. A PHP file named session-manager.php dropped into mu-plugins is characteristic of this web shell and rarely legitimate.
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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