CVE-2025-32391 HedgeDoc allows XSS possibility through malicious SVG uploads
Attackers can execute arbitrary scripts via malicious SVG uploads in HedgeDoc, potentially compromising user accounts.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-32391?
CVE-2025-32391 is a medium-severity cross-site scripting vulnerability in hedgedoc, published on 10 Apr 2025. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-79
Which versions are affected by CVE-2025-32391?
It affects 1 product.
Products include Hedgedoc Hedgedoc.
How do I fix CVE-2025-32391?
No fix has been published for CVE-2025-32391 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-32391 being exploited?
There is no known exploitation of CVE-2025-32391 in the wild and no public exploit code.
Other vulnerabilities in hedgedoc
Sources
Also known as GHSA-3983-rrqh-mvx5.