CVEvulnerability

CVE-2026-31944

7.6 HIGH Published 2026-03-13 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-13
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
7.6 HIGH — CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
Weaknesses
CWE-306

Description

LibreChat is a ChatGPT clone with additional features. From 0.8.2 to 0.8.2-rc3, The MCP (Model Context Protocol) OAuth callback endpoint accepts the redirect from the identity provider and stores OAuth tokens for the user who initiated the flow, without verifying that the browser hitting the redirect URL is logged in or that the logged-in user matches the initiator. An attacker can send the authorization URL to a victim; when the victim completes the flow, the victim’s OAuth tokens are stored on the attacker’s LibreChat account, enabling account takeover of the victim’s MCP-linked services (e.g. Atlassian, Outlook). This vulnerability is fixed in 0.8.3-rc1.

Affected configurations

• librechat librechat 0.8.2

Related

Weakness · CWE (1)

  • CWE-306 Missing Authentication for Critical Functionality weakness

References