Cross-site Scripting (XSS) Affecting librechat package, versions <0.8.7-r5


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.31% (21st percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LIBRECHAT-20416032
  • published4 Oct 2026
  • disclosed24 Jul 2026

Introduced: 24 Jul 2026

CVE-2026-66010  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Chainguard librechat to version 0.8.7-r5 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 before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.

CVSS Base Scores

version 3.1