CVE-2026-104890 (GCVE-0-2026-104890)
Vulnerability from cvelistv5
Published
2026-10-05 15:46
Modified
2026-10-07 20:50
Severity ?
7.2 (High) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Summary
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.
References
Impacted products
Vendor Product Version
Kunstmaan KunstmaanBundlesCMS Version: < 7.3.1
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