Redaxo up to 5.21.0 Mediapool mediapool.php isAllowedExtension unrestricted upload

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k0.66

Summaryinfo

A vulnerability was found in Redaxo up to 5.21.0 and classified as problematic. This impacts the function rex_mediapool::isAllowedExtension of the file redaxo/src/addons/mediapool/lib/mediapool.php of the component Mediapool. Such manipulation leads to unrestricted upload. This vulnerability is referenced as CVE-2026-53599. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Redaxo up to 5.21.0. Affected by this issue is the function rex_mediapool::isAllowedExtension of the file redaxo/src/addons/mediapool/lib/mediapool.php of the component Mediapool. The manipulation with an unknown input leads to a unrestricted upload vulnerability. Using CWE to declare the problem leads to CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-53599 since 06/09/2026. The exploitation is known to be easy. The attack may be launched remotely. The exploitation requires an enhanced level of successful authentication. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1608.002 by the MITRE ATT&CK project.

By approaching the search of inurl:redaxo/src/addons/mediapool/lib/mediapool.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 5.21.1 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Unrestricted upload
CWE: CWE-434 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Google Hack: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Redaxo 5.21.1

Timelineinfo

06/09/2026 CVE reserved
07/31/2026 +52 days Advisory disclosed
07/31/2026 +0 days VulDB entry created
07/31/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-53599 (🔒)
GCVE (CVE): GCVE-0-2026-53599
GCVE (VulDB): GCVE-100-385130

Entryinfo

Created: 07/31/2026 22:07
Changes: 07/31/2026 22:07 (56)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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