Vulnerability Description
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.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/redaxo/core/commit/462e36896bb65d292ba22d711044c23c9cfb0340
- https://github.com/redaxo/core/pull/6538
- https://github.com/redaxo/core/releases/tag/5.21.1
- https://github.com/redaxo/core/security/advisories/GHSA-98pp-vccm-qm25
- https://github.com/redaxo/core/security/advisories/GHSA-98pp-vccm-qm25
FAQ
What is CVE-2026-53599?
CVE-2026-53599 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 me...
How severe is CVE-2026-53599?
CVE-2026-53599 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-53599?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.