Vulnerability library
Security checkApril 24, 2026

Excalidraw vulnerable to XSS via Mermaid sequence diagram labels (KaTeX rendering)

Understand the exposure, see the recommended fix, and check whether your own website has related weaknesses.

Check your website

Find this and other vulnerabilities with a free scan.

Your scan runs on your computer. No account required.

Description

@excalidraw/[email protected] depends on a Mermaid conversion package version that resolves to a Mermaid release affected by CVE-2025-54881 / GHSA-7rqq-prvp-x9jh. User-supplied Mermaid sequence diagram labels could trigger XSS through Mermaid’s KaTeX label rendering path.

This is patched in @excalidraw/[email protected] by updating @excalidraw/mermaid-to-excalidraw to 2.2.2, which uses a patched Mermaid 11 release.

Recommendation

Update the @excalidraw/excalidraw package to the latest compatible version. Followings are version details:

  • Affected version(s): = 0.18.0
  • Patched version(s): 0.18.1

References

Could your website be exposed too?

SmartScanner can check your website for Excalidraw vulnerable to XSS via Mermaid sequence diagram labels (KaTeX rendering) and gives you actionable findings to investigate.

Start a free scan

Related Issues

See something that needs correcting? Let us knowUpdated April 24, 2026