CVE-2026-54030

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

25/06/2026

Last modified:

29/06/2026

Description

LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.5, LibreChat&#39;s MCP OAuth implementation does not validate that the resource parameter from OAuth Protected Resource metadata (RFC 9728) matches the configured MCP server URL, allowing a malicious MCP server to steal access tokens intended for a legitimate server. This vulnerability is fixed in 0.8.5.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N CVSS v3.1 Severity and Metrics:

Base Score: 8.00 HIGH
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): None