What’s Vulnerable › Vulnerabilities

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

• Severity: medium (CVSS 4.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-09-23 · updated 2026-10-19
• Weakness: CWE-79

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 products

• redaxo: before 5.21.2 — fixed in 5.21.2

How to fix

Upgrade to a fixed version: redaxo 5.21.2. Check the vendor advisory for mitigations.

References

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

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