XSS in Filebrowser
CVE-2026-30934
FileBrowser Quantum is a free, self-hosted, web-based file manager. Prior to 1.3.1-beta and 1.2.2-stable, Stored XSS is possible via share metadata fields (e.g., title, description) that are rendered into HTML for /public/share/<hash> without context-aware escaping. The server uses text/template instead of html/template, allowing injected scripts to execute when victims visit the share URL. This vulnerability is fixed in 1.3.1-beta and 1.2.2-stable.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.9 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L.
EPSS exploit prediction
EPSS: 0.004 (30.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.000
Affected products
- Filebrowser — versions 1.2.1, 1.3.0
- Gtsteffaniak Filebrowser — versions >= 1.3.0-beta, < 1.3.1-beta, < 1.2.2-stable
Weakness classification (CWE)
References
- github.com/gtsteffaniak/filebrowser/security/advisories/GHSA-r633-fcgp-m532 (Exploit, Vendor Advisory)
- github.com/gtsteffaniak/filebrowser/releases/tag/v1.2.2-stable (Release Notes)
- github.com/gtsteffaniak/filebrowser/releases/tag/v1.3.1-beta (Release Notes)
Frequently asked questions
- What is CVE-2026-30934?
- CVE-2026-30934 is a high-severity vulnerability in Filebrowser, classified under Cross-site Scripting. CVSS score: 8.9/10. Published 2026-03-10.
- How severe is CVE-2026-30934?
- High severity. CVSS v3 base score is 8.9 out of 10.