Possible CrushFTP CVE-2025-31161 Authentication Bypass via Webserver

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects exploitation attempts against CrushFTP CVE-2025-31161 where a request to the getUserList API function carries a forged AWS4-HMAC-SHA256 authorization referencing the crushadmin account. Huntress observed this auth-bypass request used to impersonate the built-in administrator and enumerate accounts. Successful exploitation gives an unauthenticated attacker administrative control of the file transfer server enabling data theft and follow-on intrusion.

Reporting behind it

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Possible CrushFTP CVE-2025-31161 Authentication Bypass via Webserver

Pivot detection · T1190 · 9 related

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