Vulnerability intelligence

CVE-2025-31161

CrushFTP Authentication Bypass Vulnerability

CrushFTP 10 before 10.8.4 and 11 before 11.3.1 allows authentication bypass and takeover of the crushadmin account (unless a DMZ proxy instance is used), as exploited in the wild in March and April 2025, aka "Unauthenticated HTTP(S) port access." A race condition exists in the AWS4-HMAC (compatible with S3) authorization method of the HTTP component of the FTP server. The server first verifies the existence of the user by performing a call to login_user_pass() with no password requirement. This will authenticate the session through the HMAC verification process and up until the server checks for user verification once more. The vulnerability can be further stabilized, eliminating the need for successfully triggering a race condition, by sending a mangled AWS4-HMAC header.

CVSS Score

9.8

Critical

EPSS — Exploit Probability

89%

Riskier than 100% of all CVEs

Exploitation

Confirmed in the wild

Used in ransomware campaigns

Remediation

Patch available

Federal deadline 2025-04-28

CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Deadline for federal agencies: 2025-04-28.

NVD entry Vendor patch PoC / advisory CISA KEV

1 article across 1 outlet · first covered Apr 7, 2026 · latest Apr 7, 2026

Associated threat actors

Storm-1175

Coverage timeline

Storm-1175 Deploys Medusa Ransomware at 'High Velocity'
www.darkreading.com · Apr 7, 2026