CVE-2026-31944
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.
CVSS Details
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N Threat Intelligence
Weaknesses 1
Affected Products 4
References 1
- github.com https://github.com/danny-avila/LibreChat/security/advisories/GHSA-vf7j-7mrx-hp7g
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.