CVE-2026-53599

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-31 20:16

Updated : 2026-09-09 20:55

NVD link : CVE-2026-53599

Mitre link : CVE-2026-53599

CVE.ORG link : CVE-2026-53599

JSON object : View

Products Affected

No product.

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

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