Vulnerability · Published Sep 23, 2026 · Assigned by GitHub_M

CVE-2026-63001REDAXO: Stored XSS via Unescaped Media Manager Type Name in `mediaIsInUse()`

Medium 4.8

In plain English

A medium-severity cross-site scripting in core from redaxo. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 10% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.8Medium

Exploit odds (30 days)0.2%top 90.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	redaxo/source	5.21.2	GHSA-mf2p-wjp4-99pq

Affected products (as reported)

Vendor	Product	Versions
redaxo	core	< 5.21.2

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/redaxo/core/security/advisories/GHSA-mf2p-wjp4-99pq x_refsource_CONFIRM
https://github.com/redaxo/core/pull/6581 x_refsource_MISC
https://github.com/redaxo/core/commit/2daaa3a30570bc76a82f63fd21fb8c9c2cd5dc7c x_refsource_MISC
https://github.com/redaxo/core/releases/tag/5.21.2 x_refsource_MISC