CVE-2026-40351 CRITICAL

CVE-2026-40351: FastGPT: NoSQL Injection in loginByPassword leads to Authentication Bypass

Vendor Labring
Product FastGPT
Weakness CWE-943
Published April 17, 2026
Last update April 20, 2026

CVSS base score

9.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

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

What the vulnerability does

01Description

FastGPT is an AI Agent building platform. In versions prior to 4.14.9.5, the password-based login endpoint uses TypeScript type assertion without runtime validation, allowing an unauthenticated attacker to pass a MongoDB query operator object (e.g., {"$ne": ""}) as the password field. This NoSQL injection bypasses the password check, enabling login as any user including the root administrator. This issue has been fixed in version 4.14.9.5.

Key dates

02Disclosure timeline

April 17, 2026 CVE published
April 20, 2026 Record updated