Suspicious Node.js Fileless Webshell Magic Path Request via Webserver

ATT&CK techniques

Initial Access → Persistence

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
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 the magic favicon login path used by the memory-resident Node.js webshell deployed after React2Shell CVE-2025-55182 exploitation which monkey-patches the HTTP server emit handler to run commands passed as query parameters while passing normal traffic through. Requests to this specific decoy favicon path indicate interaction with a fileless webshell.

Reporting behind it

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Suspicious Node.js Fileless Webshell Magic Path Request via Webserver

Pivot detection · T1190 · 9 related

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