GHSA-39h7-pwv7-rc3x Excalidraw vulnerable to XSS via Mermaid sequence diagram labels (KaTeX rendering)

• npm @excalidraw/excalidraw: >= 0.18.0, < 0.18.1 → fixed in 0.18.1 • npm @excalidraw/mermaid-to-excalidraw: >= 0.3.0, < 1.1.3 → fixed in 1.1.3

Impact `@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. 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/[email protected]` is patched. • Unstable `@excalidraw/excalidraw@next` has resolved to patched builds since `@excalidraw/[email protected]` on 2025-08-21. • Direct consumers of `@excalidraw/mermaid-to-excalidraw` should use `1.1.3` or later. Workarounds None. Resources • Upstream Mermaid advisory: https://github.com/mermaid-js/mermaid/security/advisories/GHSA-7rqq-prvp-x9jh • CVE-2025-54881