Malicious WordPress Webshell session-manager PHP in mu-plugins

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 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

Related detections9 linkedT1505.003 — drag to rearrange

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Malicious WordPress Webshell session-manager PHP in mu-plugins

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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