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.

Affected: Packagist: Studio-42/elFinder

### Summary

elFinder provides `uploadDeny` and `uploadAllow` options in its connector configuration to restrict which MIME types may be uploaded. When `uploadDeny` includes `text/x-php`, direct upload of `.php`, `.phtml`, and `.phar` files is correctly blocked. However, the `extract` command (ZIP decompression) internally calls `checkExtractItems()`, which invokes `mimetypeInternalDetect()` directly without passing the result through `mimeTypeNormalize()`. Because `phtml`, `phar`, and similar PHP-executable extensions are absent from `mime.types`, they are not resolved to `text/x-php` at the detection stage, causing the MIME filter to be silently bypassed. An attacker who is permitted to upload ZIP archives can therefore extract PHP-executable files into the web-accessible `files/` directory. If the server is configured to execute the affected extension (e.g., `.phtml`, `.phar`) as PHP — which is the case in common Apache and Nginx deployments — this results in Remote Code Execution.

---

### Details

elFinder's MIME validation pipeline for **direct uploads** (`upload` command) is:

``` mimetype() └─ mimetypeInternalDetect() // stage 1: extension → MIME via mime.types └─ mimeTypeNormalize() // stage 2: apply staticMimeMap phtml:* → text/x-php phar:* → text/x-php php5:* → text/x-php └─ allowPutMime() // blocked: text/x-php ∈ uploadDeny ```

The `extract` command (`checkExtractItems()` in `elFinderVolumeDriver.class.php`, lin…