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OpenAdvisories
Medium · 5.3 CVE-2025-66452 EUVD-2025-202928

LibreChat's lack of JSON parsing error handling can lead to XSS

Published Dec 11, 2025 · Updated Dec 12, 2025 · Assigned by GitHub_M

Description

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

VendorProductAffectedFixed
danny-avila LibreChat <= 0.8.1 —

References