CVE-2026-44259 efw4.X: Stored XSS via previewServlet
Attackers can execute arbitrary JavaScript in victims' browsers via stored XSS in the previewServlet, potentially leading to session hijacking or data theft.
- 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-2026-44259?
CVE-2026-44259 is a medium-severity cross-site scripting vulnerability in efwGrp efw4.X, published on 12 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
efw4.X is an Enterprise Framework for Web. Prior to 4.08.010, the previewServlet serves files with their detected MIME type based on file extension, without any content sanitization or security headers. Files with .html, .htm, or .svg extensions are served as text/html or image/svg+xml respectively, causing any embedded JavaScript to execute in the victim's browser within the application's origin. This vulnerability is fixed in 4.08.010.
Weakness: CWE-80
Which versions are affected by CVE-2026-44259?
How do I fix CVE-2026-44259?
No fix has been published for CVE-2026-44259 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-2026-44259 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-44259 exists.
Sources
Also known as GHSA-hw67-p3gw-rrmj.