GHSA-39h7-pwv7-rc3x
Excalidraw vulnerable to XSS via Mermaid sequence diagram labels (KaTeX rendering)
GHSA-39h7-pwv7-rc3x is a vulnerability with no CVSS score yet in @excalidraw/excalidraw, published April 24, 2026. No source lists public exploit code. Fixed in @excalidraw/excalidraw 0.18.1.
- Severity
- UnratedNo CVSS score yet
- Exploit chance
- UnscoredNo EPSS score yet
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
0.18.1@excalidraw/excalidraw +2 more
Description
Impact
@excalidraw/excalidraw@0.18.0 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/excalidraw@0.18.1 by updating @excalidraw/mermaid-to-excalidraw to 2.2.2, which uses a patched Mermaid 11 release.
Moderate severity as this XSS requires manual user action - pasting unsafe Mermaid diagram into the Excalidraw editor. No semi-automated attack vector exists by default (such as accessing a link).
Patches
- Stable
@excalidraw/excalidraw@0.18.1is patched. - Unstable
@excalidraw/excalidraw@nexthas resolved to patched builds since@excalidraw/excalidraw@0.18.0-f29edfon 2025-08-21. - Direct consumers of
@excalidraw/mermaid-to-excalidrawshould use1.1.3or later.
Workarounds
None.
Resources
- Upstream Mermaid advisory: https://github.com/mermaid-js/mermaid/security/advisories/GHSA-7rqq-prvp-x9jh
- CVE-2025-54881
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@excalidraw/excalidrawnpm | 0.18.0 to 0.18.0 | 0.18.1 |
@excalidraw/mermaid-to-excalidrawnpm | 0.3.0 up to 1.1.3 | 1.1.3 |
@excalidraw/excalidrawnpm | 0.18.0 up to 0.18.1 | 0.18.1 |
What each source reports
GitHub AdvisoriesNo score
Excalidraw vulnerable to XSS via Mermaid sequence diagram labels (KaTeX rendering)
Impact
@excalidraw/excalidraw@0.18.0 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/excalidraw@0.18.1 by updating @excalidraw/mermaid-to-excalidraw to 2.2.2, which uses a patched Mermaid 11 release.
Moderate severity as this XSS requires manual user action - pasting unsafe Mermaid diagram into the Excalidraw editor. No semi-automated attack vector exists by default (such as accessing a link).
Patches
- Stable
@excalidraw/excalidraw@0.18.1is patched. - Unstable
@excalidraw/excalidraw@nexthas resolved to patched builds since@excalidraw/excalidraw@0.18.0-f29edfon 2025-08-21. - Direct consumers of
@excalidraw/mermaid-to-excalidrawshould use1.1.3or later.
Workarounds
None.
Resources
- Upstream Mermaid advisory: https://github.com/mermaid-js/mermaid/security/advisories/GHSA-7rqq-prvp-x9jh
- CVE-2025-54881
- Record
GHSA-39h7-pwv7-rc3x- Weakness
- CWE-79, CWE-1395
- Updated
- 2026-11-02
OSVNo score
Excalidraw vulnerable to XSS via Mermaid sequence diagram labels (KaTeX rendering)
Impact
@excalidraw/excalidraw@0.18.0 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/excalidraw@0.18.1 by updating @excalidraw/mermaid-to-excalidraw to 2.2.2, which uses a patched Mermaid 11 release.
Moderate severity as this XSS requires manual user action - pasting unsafe Mermaid diagram into the Excalidraw editor. No semi-automated attack vector exists by default (such as accessing a link).
Patches
- Stable
@excalidraw/excalidraw@0.18.1is patched. - Unstable
@excalidraw/excalidraw@nexthas resolved to patched builds since@excalidraw/excalidraw@0.18.0-f29edfon 2025-08-21. - Direct consumers of
@excalidraw/mermaid-to-excalidrawshould use1.1.3or later.
Workarounds
None.
Resources
- Upstream Mermaid advisory: https://github.com/mermaid-js/mermaid/security/advisories/GHSA-7rqq-prvp-x9jh
- CVE-2025-54881
- Record
GHSA-39h7-pwv7-rc3x- Weakness
- CWE-1395, CWE-79
- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.