What is the CVSS score of CVE-2025-31161?

CVE-2025-31161 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 86.2%.

Which versions of Crushftp are affected by CVE-2025-31161?

Organizations using CrushFTP 10 before 10.8.4 and 11 before 11.3.1 face critical risk from CVE-2025-31161 rated CVSS 9.8.

Is there a public PoC exploit available for CVE-2025-31161?

Yes, a public proof-of-concept exploit is available for CVE-2025-31161. Prioritise patching immediately. EPSS: 86.2%.

How to fix or mitigate CVE-2025-31161?

Within 24 hours: Identify all affected systems and apply vendor patches immediately. Monitor vendor channels for patch availability.

Crushftp CVE-2025-31161

CRITICAL

Authentication Bypass by Primary Weakness (CWE-305)

2025-04-03 cve@mitre.org

Authentication Bypass Crushftp

9.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 18:34 vuln.today

Added to CISA KEV

Oct 31, 2025 - 22:04 cisa

CISA KEV

PoC Detected

Oct 31, 2025 - 22:04 vuln.today

Public exploit code

CVE Published

Apr 03, 2025 - 20:15 nvd

CRITICAL 9.8

DescriptionCVE.org

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. By providing only the username and a following slash (/), the server will successfully find a username, which triggers the successful anypass authentication process, but the server will fail to find the expected SignedHeaders entry, resulting in an index-out-of-bounds error that stops the code from reaching the session cleanup. Together, these issues make it trivial to authenticate as any known or guessable user (e.g., crushadmin), and can lead to a full compromise of the system by obtaining an administrative account.

AnalysisAI

CrushFTP 10 and 11 contain an authentication bypass allowing takeover of the crushadmin account through a race condition in the AWS4-HMAC authorization method, massively exploited in March-April 2025.

Technical ContextAI

The CWE-305 race condition in the AWS4-HMAC digest authentication allows attackers to win a race during credential validation, authenticating as the crushadmin account without knowing the password.