CVE-2025-32391 Information

Description

HedgeDoc is an open source real-time collaborative markdown notes application. Prior to 1.10.3 a malicious SVG file uploaded to HedgeDoc results in the possibility of XSS when opened in a new tab instead of the editor itself. The XSS is possible by exploiting the JSONP capabilities of GitHub Gist embeddings. Only instances with the local filesystem upload backend or special configurations where the uploads are served from the same domain as HedgeDoc are vulnerable. This vulnerability is fixed in 1.10.3. When upgrading to HedgeDoc 1.10.3 is not possible instance owners could add the following headers for all routes under /uploads as a first-countermeasure: Content-Disposition: attachment and Content-Security-Policy: default-src ’none’. Additionally the external URLs in the script-src attribute of the Content-Security-Policy header should be removed.

Reference

https://github.com/hedgedoc/hedgedoc/commit/0636b5c20b7097afccfa6641830352ad068ef964 https://github.com/hedgedoc/hedgedoc/commit/3f520ea59abf912c66d7443cb99f29a567c47748 https://github.com/hedgedoc/hedgedoc/commit/d2585fbd3b398b3359f6f88aa1fda8f4ecf2f78d https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-3983-rrqh-mvx5