Kunstmaan CMS: MediaBundle extension blacklist bypass allows authenticated administrators to upload executable PHP files leading to remote code execution

[ Description ]Official description

Kunstmaan CMS is an open source content management system based on the Symfony framework. Prior to 7.3.2, src/Kunstmaan/MediaBundle/Helper/File/FileHandler.php performs the blacklisted_extensions check case-sensitively in FileHandler::getFilePath and lowercases the stored extension afterward. An authenticated backend user with media access can upload a mixed-case executable extension such as PHP that bypasses the check and is stored in the web-accessible media directory with an executable lowercase extension. The default blacklist also omits several server-executable extension types, allowing the same code-execution impact where the web server executes uploaded files. This issue is fixed in version 7.3.2.

[ Fixes ]Fixes and patches

• kunstmaan/media-bundle 7.3.2Fixed version · GitHub Advisories · composer package kunstmaan/media-bundle: upgrade to 7.3.2 or later (affected < 7.3.2)
• kunstmaan/bundles-cms 7.3.2Fixed version · GitHub Advisories · composer package kunstmaan/bundles-cms: upgrade to 7.3.2 or later (affected < 7.3.2)

[ Packages ]Affected open-source packages

• kunstmaan/media-bundle composerAffected < 7.3.2 · fixed in 7.3.2 · GHSA-p279-5wcv-45vq
• kunstmaan/bundles-cms composerAffected < 7.3.2 · fixed in 7.3.2 · GHSA-p279-5wcv-45vq

[ References ]References

• github.com/Kunstmaan/KunstmaanBundlesCMS/commit/1bbdfdeac8e7e91506b1a9271360b9b68d7690d3
• github.com/Kunstmaan/KunstmaanBundlesCMS/releases/tag/7.3.2
• github.com/Kunstmaan/KunstmaanBundlesCMS/security/advisories/GHSA-p279-5wcv-45vq