CVE-2026-66010 (Medium) detected in dompurify-3.4.1.tgz

[mend-bolt-for-github]

CVE-2026-66010 - Medium Severity Vulnerability

Vulnerable Library - dompurify-3.4.1.tgz

DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. It's written in JavaScript and works in all modern browsers (Safari, Opera (15+), Internet Explorer (10+), Firefox and Chrome - as well as almost anything else usin

Library home page: https://registry.npmjs.org/dompurify/-/dompurify-3.4.1.tgz

Path to dependency file: /ui/package.json

Path to vulnerable library: /ui/node_modules/.pnpm/dompurify@3.4.1/node_modules/dompurify/package.json

Dependency Hierarchy:

• @⁠postgres.ai/ce-4.0.3.tgz (Root Library)
  • react-4.7.0.tgz
    • monaco-editor-0.55.1.tgz
      • ❌ dompurify-3.4.1.tgz (Vulnerable Library)

Found in base branch: master

Vulnerability Details

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.

Publish Date: 2026-07-24

URL: CVE-2026-66010

CVSS 3 Score Details (6.1)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: Required
  • Scope: Changed
• Impact Metrics:
  • Confidentiality Impact: Low
  • Integrity Impact: Low
  • Availability Impact: None

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: GHSA-c2j3-45gr-mqc4

Release Date: 2026-07-24

Fix Resolution: dompurify - 3.4.12,dompurify - 3.4.12,https://github.com/cure53/DOMPurify.git - 3.4.12

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