LibreChat — Vulnerability (CVE-2026-54040)
Date: 2026-06
Affected: librechat/librechat
Attack vector: auth-bypass
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-54040
CWE: CWE-306
CVSS: 5.9 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N)

LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.4-rc1, the POST /api/auth/2fa/backup/regenerate endpoint regenerates all 2FA backup codes without requiring any TOTP token or existing backup code verification. An attacker with a stolen session token can silently replace a victim's backup codes and use them to bypass 2FA login or disable 2FA entirely. This vulnerability is fixed in 0.8.4-rc1.


Mitigations:

Architectural layers (MAESTRO):