REDAXO: Stored XSS via Unescaped Media Manager Type Name in mediaIsInUse()

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.8 · CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

EPSS

• CVE-2026-63001: 0.20% estimated exploitation activity in the next 30 days; percentile 9.51 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A stored cross-site scripting (XSS) vulnerability exists in REDAXO CMS 5.x. When an administrator attempts to delete a media file that is referenced by a Media Manager effect, the warning message rendered in the backend includes the type's name field without HTML escaping. An attacker with access to the Media Manager addon can store an XSS payload as a type name; the payload executes in the browser of any administrator who subsequently tries to delete a media file linked to that type's effects. This can lead to session hijacking and full backend account takeover. --- Details File: redaxo/src/addons/mediamanager/lib/mediamanager.php Function: mediaIsInUse() — registered on the MEDIAISINUSE extension point in boot.php When rexmediaservice::deleteMedia() is called, it invokes rexmediapool::mediaIsInUse($filename), which fires the MEDIAISINUSE extension point. The mediamanager addon's handler queries all effects whose parameters JSON contains the filename, then constructs an HTML…

Published by the source

23 Sep 2026, 14:04 UTC

Last modified by the source

23 Sep 2026, 14:15 UTC

Source last checked

26 Oct 2026, 14:53 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-mf2p-wjp4-99pq

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-mf2p-wjp4-99pq

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# Patch Next advisory brief: CVE-2026-63001

Advisory: REDAXO: Stored XSS via Unescaped Media Manager Type Name in `mediaIsInUse()`
IDs: CVE-2026-63001, GHSA-mf2p-wjp4-99pq
Record: https://patchnext.com/advisories/cve-2026-63001 (revision 2, source checked 26 Oct 2026, 14:53 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: redaxo/source 5.21.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist redaxo/source: affected <= 5.21.1; fixed in 5.21.2

## Suggested inspection (read-only)
- Packagist redaxo/source: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on redaxo/source.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-mf2p-wjp4-99pq (OSV record GHSA-mf2p-wjp4-99pq lists affected ranges: Packagist redaxo/source >=0 <5.21.2 (fixed))
- Verified: https://github.com/advisories/GHSA-mf2p-wjp4-99pq (GitHub-reviewed advisory GHSA-mf2p-wjp4-99pq lists affected ranges: Packagist redaxo/source >=0 <=5.21.1)

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