CVE-2026-74793 justhtml before 3.11.0 XSS via selectedcontent projection
Attackers can inject malicious scripts via SVG or MathML elements in justhtml, leading to cross-site scripting attacks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-74793?
CVE-2026-74793 is a medium-severity cross-site scripting vulnerability in EmilStenstrom justhtml, published on 23 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
justhtml before 3.11.0 contains a cross-site scripting vulnerability where the default sanitizer bypasses event handler removal in selectedcontent projections. Attackers can inject SVG or MathML elements with event handlers that are cloned and reinserted into output without sanitization, enabling stored or reflected XSS attacks.
Weakness: CWE-79
Which versions are affected by CVE-2026-74793?
How do I fix CVE-2026-74793?
No fix has been published for CVE-2026-74793 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-2026-74793 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-74793 exists.
Sources
Also known as GHSA-gjf2-f4jc-69xf, GHSA-h7rw-29pr-mcj6.