XSS in Redaxo Core
CVE-2026-63001
REDAXO is a PHP-based content management system. Prior to 5.21.2, the mediaIsInUse() handler in redaxo/src/addons/media_manager/lib/media_manager.php inserts a Media Manager type name into raw backend warning HTML without escaping it when invoked through MEDIA_IS_IN_USE. An administrator with Media Manager access can store HTML in a type name, and the payload executes in another administrator's browser when that administrator tries to delete media referenced by the type's effects, enabling session theft or unauthorized backend actions. This issue is fixed in version 5.21.2.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/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
- Redaxo Core — versions < 5.21.2
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-63001?
- CVE-2026-63001 is a medium-severity vulnerability in Redaxo Core, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2026-09-23.
- How severe is CVE-2026-63001?
- Medium severity. CVSS v3 base score is 4.8 out of 10.