CVE-2026-54030
LibreChat
- Severity
- High
- Published
- June 25, 2026
- Last modified
- June 29, 2026
LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.5, LibreChat'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.
CVSS vector CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
Weakness
- CWE-346 Origin validation error
References
- github.comExploitVendor Advisory
- github.comExploitVendor Advisory
Listed in
More LibreChat CVEs
Users with only `VIEW` access to an MCP server can retrieve the server's decrypted admin-managed secrets through `GET /api/mcp/servers` and `GET /api/mcp/servers/:serverName`.
The Model Context Protocol (MCP) server integration resolves ${VAR} placeholders against the server's process.env during Zod schema validation of user-supplied MCP server URLs.
User-created MCP (Model Context Protocol) servers can include arbitrary HTTP headers that undergo credential placeholder substitution.
Versions 0.8.2-rc2 through 0.8.2 are vulnerable to a server-side request forgery (SSRF) attack when using agent actions or MCP.