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

Vulnerability 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.

References

• https://github.com/danny-avila/LibreChat/security/advisories/GHSA-q6c5-gvj5-c264