Cross-site Scripting (XSS) Affecting librechat package, versions <0.8.7-r1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.18% (8th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LIBRECHAT-18300134
  • published25 Jul 2026
  • disclosed23 Jul 2026

Introduced: 23 Jul 2026

NewCVE-2026-65900  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Chainguard librechat to version 0.8.7-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.

DOMPurify versions >=3.0.0 and before 3.4.8, when configured with SAFE_FOR_TEMPLATES together with a DOM output mode (RETURN_DOM, RETURN_DOM_FRAGMENT, or IN_PLACE), fail to strip template expressions (e.g. ${evil}, {{evil}}, <%evil%>) inside <template> element content. The final normalization/scrub pass (_scrubTemplateExpressions) uses a NodeIterator and node.normalize() that do not descend into template.content, so expressions that only form after adjacent text nodes merge survive sanitization. This bypasses SAFE_FOR_TEMPLATES and can allow a downstream template engine to evaluate attacker-supplied expressions. The string output path is not affected.

CVSS Base Scores

version 3.1