Cross-site Scripting (XSS) Affecting librechat package, versions <0.8.2-r1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.05% (17th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LIBRECHAT-14459506
  • published17 Dec 2025
  • disclosed11 Dec 2025

Introduced: 11 Dec 2025

CVE-2025-66452  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Chainguard librechat to version 0.8.2-r1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream librechat package and not the librechat package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1