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ATutor <= 2.2 (edit_marks.php) PHP Code Injection Vulnerability
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[-] Software Link:
http://www.atutor.ca/
[-] Affected Versions:
Version 2.2 and prior versions.
[-] Vulnerability Description:
The vulnerable code is located in the /mods/_standard/gradebook/edit_marks.php script:
54. if (isset($_GET['asc']))
55. {
56. $order = 'asc';
57. $order_col = $addslashes($_GET['asc']);
58. }
59. else if (isset($_GET['desc'])) {
60. $order = 'desc';
61. $order_col = $addslashes($_GET['desc']);
[...]
185. if ((isset($_GET["asc"]) || isset($_GET["desc"])) && $order_col <> "name")
186. {
187. $sort = '$grades['.$order_col.'], SORT_'.strtoupper($order).', $selected_students ...
188.
189. foreach($selected_tests as $test)
190. {
191. if ($test["gradebook_test_id"] <> $order_col)
192. $sort .= ', $grades['.$test["gradebook_test_id"].'], SORT_'.strtoupper($order);
193. }
194. $sort='array_multisort('.$sort.');';
195. eval($sort);
196. }
User input passed through the "asc" or "desc" GET parameters is not properly sanitized before being used in a
call to the "eval()" function at line 195. This can be exploited to inject and execute arbitrary PHP code.
Successful exploitation of this vulnerability requires an account with the "AT_PRIV_GRADEBOOK" privilege.
[-] Solution:
No official solution is currently available.
[-] Disclosure Timeline:
[06/10/2014] - Vendor notified
[09/10/2014] - Vendor response stating this issue has been added to the bug tracker and it is relatively minor
[13/10/2014] - Vendor replied saying he is not able to reproduce the issue and asked for further details
[29/10/2014] - Further exploitation details have been provided to the vendor
[11/11/2014] - Vendor replied saying he still is not able to reproduce the issue and asked for fix suggestions
[11/11/2014] - Some fix suggestions have been provided to the vendor
[30/09/2015] - CVE number requested
[05/10/2015] - CVE number assigned
[06/10/2015] - After one year still no official solution available
[04/11/2015] - Public disclosure
[-] CVE Reference:
The Common Vulnerabilities and Exposures project (cve.mitre.org)
has assigned the name CVE-2015-7712 to this vulnerability.
[-] Credits:
Vulnerability discovered by Egidio Romano.
[-] Original Advisory:
http://karmainsecurity.com/KIS-2015-08
