elFinder is an open-source file manager for web, written in JavaScript using jQuery UI. Prior to 2.1.70, checkExtractItems() in php/elFinderVolumeDriver.class.php calls mimetypeInternalDetect() without passing the result through mimeTypeNormalize(). Because the .phtml, .phar, .php5, and .php3 extensions are absent from mime.types, the staticMimeMap entries that map them to text/x-php are not applied, and allowPutMime() permits extraction even when uploadDeny blocks text/x-php. An attacker with ZIP upload permission can extract PHP-executable files into a web-accessible files/ directory and achieve remote code execution when the server executes those extensions. This issue is fixed in version 2.1.70.

A critical vulnerability in elFinder (open-source web file manager) prior to version 2.1.70 allows remote code execution via a MIME type normalization bypass. The checkExtractItems() function fails to pass results through mimeTypeNormalize(), causing PHP-executable extensions (.phtml, .phar, .php5, .php3) to bypass upload denial rules. Attackers with ZIP upload permissions can extract PHP files into web-accessible directories and execute arbitrary code. The root cause is that these extensions are absent from mime.types, so staticMimeMap entries mapping them to text/x-php are never applied. The allowPutMime() function then incorrectly permits extraction even when uploadDeny blocks text/x-php. The vulnerability is fixed in elFinder version 2.1.70 with two separate commits addressing the issue.