High 7.5Published Jul 31, 2026

CVE-2026-53599Redaxo has a Mediapool isAllowedExtension bypass via multi-segment filename that leads to authenticated RCE on Apache mod_php multi-extension handlers

Updated under an hour ago (2026-10-19 10:10 UTC)

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It affects redaxo core. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for redaxo core

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-434
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Jul 31, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

redaxo core redaxo:core (from the name)	from 5.18.2, < 5.21.1	CNA record

References

https://github.com/redaxo/core/security/advisories/GHSA-98pp-vccm-qm25x-refsource-confirm
https://github.com/redaxo/core/pull/6538x-refsource-misc
https://github.com/redaxo/core/commit/462e36896bb65d292ba22d711044c23c9cfb0340x-refsource-misc
https://github.com/redaxo/core/releases/tag/5.21.1x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.