Auth bypass in Xibosignage Xibo-Cms
CVE-2026-50539
Xibo is an open source digital signage platform with a web content management system and Windows display player software. Prior to 4.4.3, missing object-level authorization on `/notification/export/{id}` allows an authenticated user to download attachments from any notification, including notifications created by administrators, by iterating over `sequential notification IDs`. Exploitation requires access to the `Notification Centre` to view past notifications, a privilege granted to non-administrators as standard. This issue is fixed in version 4.4.3.
Vulnerability class: Broken Access Control
Published .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Xibosignage Xibo-Cms — versions < 4.4.3
Weakness classification (CWE)
References
- github.com/xibosignage/xibo-cms/security/advisories/GHSA-p4pg-v57g-7jf6
- github.com/xibosignage/xibo-cms/pull/3487
- github.com/xibosignage/xibo-cms/commit/13ed6e6bf3c15a93089b4fd2148379888ee82d74
- github.com/xibosignage/xibo-cms/commit/1dcc3f2de6dc7861e7dbb5148e94f14ebb1513b3
- github.com/xibosignage/xibo-cms/releases/tag/4.4.3
- github.com/xibosignage/xibo-cms/releases/tag/4.5.0-beta
Frequently asked questions
- What is CVE-2026-50539?
- CVE-2026-50539 is a medium-severity vulnerability in Xibosignage Xibo-Cms, classified under Missing Authorization. CVSS score: 6.5/10. Published 2026-10-28.
- How severe is CVE-2026-50539?
- Medium severity. CVSS v3 base score is 6.5 out of 10.