high7.5
CVE-2026-53599
Redaxo has a Mediapool isAllowedExtension bypass via multi-segment filename that leads to authenticated RCE on Apache mod_php multi-extension handlers
Impact
REDAXO is a PHP-based content management system. From 5.18.2 until 5.21.1, rex_mediapool::isAllowedExtension in redaxo/src/addons/mediapool/lib/mediapool.php lets an authenticated backend user with media[upload] permission upload a JPEG/PHP polyglot named shell.php.any.jpg, which web servers with multi-extension PHP handlers can execute as the web-server user. This issue is fixed in version 5.21.1.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | redaxo/source | >= 5.18.2, < 5.21.1 | 5.21.1 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-98pp-vccm-qm25
- https://github.com/redaxo/core/security/advisories/GHSA-98pp-vccm-qm25
- https://github.com/redaxo/core/pull/6538
- https://github.com/redaxo/core/commit/462e36896bb65d292ba22d711044c23c9cfb0340
- https://github.com/redaxo/core/releases/tag/5.21.1