redaxscript 2.5.0: Code Execution
Date: 2015-12-02 10:39:201. Introduction
| Affected Product: | redaxscript 2.5.0 |
| Fixed in: | module has been removed in version 2.6.0 |
| Fixed Version Link: | n/a |
| Vendor Contact: | info@redaxmedia.com |
| Vulnerability Type: | Code Execution |
| Remote Exploitable: | Yes |
| Reported to vendor: | 10/02/2015 |
| Disclosed to public: | 12/02/2015 |
| Release mode: | Coordinated release |
| CVE: | n/a |
| Credits | Tim Coen of Curesec GmbH |
2. Overview
CVSS
High 9.0 AV:N/AC:L/Au:S/C:C/I:C/A:C
Description
The module file_manager allows for file uploads, and uses exif_imagetype to check the validity of the file.
By setting the first bytes of the uploaded file to that of a valid image type, an attacker can easily bypass this check and thus upload files of dangerous type.
It should be noted that only files with the name index.php will be executed, as access to all other PHP files is forbidden by a htaccess file.
An account that has access to the module "File manager" is needed to exploit this issue.
3. Code
/modules/file_manager/index.php
function file_manager_upload($directory = '')
{
$file = $_FILES['file']['tmp_name'];
$file_name = file_manager_clean_file_name($_FILES['file']['name']);
$file_size = $_FILES['file']['size'];
/* validate post */
if (function_exists('exif_imagetype'))
{
if (exif_imagetype($file) == '')
{
$error = l('file_type_limit', '_file_manager') . l('point');
}
}
4. Solution
To mitigate this issue please remove the file_manager module.
5. Report Timeline
| 10/02/2015 | Informed Vendor about Issue |
| 11/15/2015 | Vendor removes affected module |
| 12/02/2015 | Disclosed to public |