Vulnerability · Published May 12, 2026 · Assigned by GitHub_M

CVE-2026-44259efw4.X: Stored XSS via previewServlet

Medium 4.6

In plain English

A medium-severity security flaw in efw4.X from efwGrp. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities).

Severity (CVSS 3.1)4.6Medium

Exploit odds (30 days)0.2%top 94.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

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.

Affected products (as reported)

Vendor	Product	Versions
efwGrp	efw4.X	< 4.08.010

Weakness: CWE-80 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

References

https://github.com/efwGrp/efw4.X/security/advisories/GHSA-hw67-p3gw-rrmj x_refsource_CONFIRM