CVE-2025-66452: Librechat

Medium severity, CVSS 6.1. EPSS: 0.2% chance of exploitation in the next 30 days.

LibreChat is a ChatGPT clone with additional features. In versions 0.8.0 and below, there is no handler for JSON parsing errors; SyntaxError from express.json() includes user input in the error message, which gets reflected in responses. User input (including HTML/JavaScript) can be exposed in error responses, creating an XSS risk if Content-Type isn't strictly enforced. This issue does not have a fix at the time of publication.

Affected products

• Librechat Librechat: up to and including 0.8.0

Published 2025-12-11. Last modified 2026-10-07.