Author: @Ambulong
Security Team ChaMd5 disclose a Local File Inclusion vulnerability in phpMyAdmin latest version 4.8.1. And the exploiting of this vulnerability may lead to Remote Code Execution.
In this article, we will use VulnSpy’s online phpMyAdmin environment to demonstrate the exploit of this vulnerability.
VulnSpy’s online phpMyAdmin environment address: http://www.vulnspy.com/phpmyadmin-4.8.1/
Vulnerability Details
1.Line 54-63 in file /index.php:
|
1
2
3
4
5
6
7
8
9
10
|
// If we have a valid target, let’s load that script instead
if (! empty($_REQUEST[‘target’])
&& is_string($_REQUEST[‘target’])
&& ! preg_match(‘/^index/’, $_REQUEST[‘target’])
&& ! in_array($_REQUEST[‘target’], $target_blacklist)
&& Core::checkPageValidity($_REQUEST[‘target’])
) {
include $_REQUEST[‘target’];
exit;
}
|
2.Core::checkPageValidity in /libraries/classes/Core.php
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
/**
* boolean phpMyAdmin.Core::checkPageValidity(string &$page, array $whitelist)
*
* checks given $page against given $whitelist and returns true if valid
* it optionally ignores query parameters in $page (script.php?ignored)
*
* @param string &$page page to check
* @param array $whitelist whitelist to check page against
*
* @return boolean whether $page is valid or not (in $whitelist or not)
*/
public static function checkPageValidity(&$page, array $whitelist = [])
{
if (empty($whitelist)) {
$whitelist = self::$goto_whitelist;
}
if (! isset($page) || !is_string($page)) {
return false;
}
if (in_array($page, $whitelist)) {
return true;
}
$_page = mb_substr(
$page,
0,
mb_strpos($page . ‘?’, ‘?’)
);
if (in_array($_page, $whitelist)) {
return true;
}
$_page = urldecode($page);
$_page = mb_substr(
$_page,
0,
mb_strpos($_page . ‘?’, ‘?’)
);
if (in_array($_page, $whitelist)) {
return true;
}
return false;
}
|
Core::checkPageValidity can be bypassed by using by double encoding like
.
Exploit
An attacker can use this vulnerability to include session file to lauching a Remote Code Execution vulnerability.
1.Use username root, password toor log into phpmyadmin.
2.Run SQL query
3.Get your Session ID
Session ID is the item
in your cookie.
4.Include the session file
