Drupal 6.22 / SuperCron 6.x-1.3 Cross Site Scripting

`-----BEGIN PGP SIGNED MESSAGE-----  
Hash: SHA1  
  
Description of Vulnerability:  
- -----------------------------  
Drupal (http://drupal.org) is a robust content management system (CMS)  
written in PHP and MySQL. The Drupal SuperCron module  
(https://drupal.org/project/supercron), created by 63 Reasons  
(http://www.63reasons.com/), "is a complete replacement for Drupal's  
built-in Cron functionality." The SuperCron module contains a  
persistent arbitrary HTML injection vulnerability (also known as cross  
site scripting, or XSS) due to the fact that it fails to user supplied  
third party data before display.  
  
Systems affected:  
- -----------------  
Drupal 6.22 with SuperCron 6.x-1.3 was tested and shown to be vulnerable  
  
Impact  
- ------  
Attackers could inject arbitrary scripts into pages affecting site  
users. This could result in administrative account compromise leading  
to web server process compromise. A more likely scenario would be for  
an attacker to inject hidden content (such as iframes, applets, or  
embedded objects) that would attack client browsers in an attempt to  
compromise site users' machines. This vulnerability could also be  
used to launch cross site request forgery (XSRF) attacks against the  
site that could have other unexpected consequences.  
  
Mitigating factors:  
- -------------------  
In order to exploit this vulnerability the attacker must have  
permissions to access administration pages. This is an extremely  
loose permission given the impact not only of this vulnerability but  
also of the module's general functionality.  
  
Proof of concept:  
- -----------------  
1. Install Drupal 6-22 and install and enable SuperCron 6.x-1.3  
2. Navigate to SuperCron's Firewall settings at  
?q=admin/settings/supercron/firewall  
3. Enable the firewall  
4. Expand the 'Insert IP' portion of the form  
5. Insert "<script>alert('xss');</script>" for the IP address and  
click the "Insert" button  
6. Observe the transient JavaScript in the Drupal confirmation message  
7. Persistent JavaScript is rendered at  
?q=admin/settings/supercron/firewall  
  
Patch:  
- ------------------------------------------  
Applying the following patch mitigates this issue in version 6.x-1.3  
(and adds new permissions for the module)  
  
- --- supercron/supercron.module 2009-06-15 02:55:20.000000000 -0400  
+++ supercron.fixed/supercron.module 2011-10-30 00:34:24.316054217 -0400  
@@ -23,7 +23,7 @@ function supercron_menu() {  
'description' => t('Configure how Cron behaves, which cron hooks  
are called and in what order, capture debugging information and  
parallelize tasks.'),  
'page callback' => 'drupal_get_form',  
'page arguments' => array('supercron_settings'),  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
);  
$items['admin/settings/supercron/'] = array(  
'title' => t('Settings'),  
@@ -34,20 +34,20 @@ function supercron_menu() {  
'title' => t('Firewall'),  
'page callback' => 'drupal_get_form',  
'page arguments' => array('supercron_firewall_form'),  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_LOCAL_TASK,  
'parent' => 'admin/settings/supercron'  
);  
$items['admin/settings/supercron/firewall/delete'] = array(  
'page callback' => 'supercron_firewall_delete',  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_CALLBACK  
);  
$items['admin/settings/supercron/output/%'] = array(  
'title' => t('Cron output in module: '),  
'page callback' => 'supercron_output',  
'page arguments' => array(4),  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_CALLBACK,  
);  
  
@@ -55,7 +55,7 @@ function supercron_menu() {  
'title' => t('Cron exceptions in module: '),  
'page callback' => 'supercron_exception',  
'page arguments' => array(4),  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_CALLBACK,  
);  
  
@@ -63,20 +63,20 @@ function supercron_menu() {  
'title' => t('Call individual cron handlers'),  
'page callback' => 'supercron_invoke_one',  
'page arguments' => array(4, 5),  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_CALLBACK,  
);  
  
$items[SUPERCRON_INVOKE_ALL] = array(  
'page callback' => 'supercron_drupal_cron_run',  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_CALLBACK,  
'file' => 'cron.inc',  
);  
  
$items['admin/reports/status/run-cron'] = array(  
'page callback' => 'supercron_drupal_cron_run',  
- - 'access arguments' => array('access administration pages'),  
+ 'access arguments' => array('administer SuperCron'),  
'type' => MENU_CALLBACK,  
'file' => 'cron.inc',  
);  
@@ -137,6 +137,12 @@ function supercron_firewall_delete($id)  
drupal_goto('admin/settings/supercron/firewall');  
}  
  
+function supercron_firewall_form_validate($form, &$form_state) {  
+ if (! preg_match('/\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/',  
$form_state['values']['ip']) > 0) {  
+ form_set_error('', t('Invalid IP address.'));  
+ }  
+}  
+  
function supercron_firewall_form(&$form_state) {  
$firewall_enabled =  
variable_get(SUPERCRON_FIREWALL_ENABLED_VARIABLE, FALSE);  
$form['firewall_enable_field'] = array(  
@@ -206,11 +212,11 @@ function supercron_firewall_form(&$form_  
$result = db_query('SELECT * FROM {supercron_ips}');  
while ($ip = db_fetch_object($result)) {  
if ($firewall_enabled) {  
- - $form[$ip->iid]['title'] = array('#value' => $ip->ip);  
+ $form[$ip->iid]['title'] = array('#value' =>  
check_plain($ip->ip));  
$form[$ip->iid]['delete'] = array('#value' => l(t('delete'),  
"admin/settings/supercron/firewall/delete/" . $ip->iid));  
}  
else {  
- - $form[$ip->iid]['title'] = array('#value' => $ip->ip);  
+ $form[$ip->iid]['title'] = array('#value' =>  
check_plain($ip->ip));  
$form[$ip->iid]['delete'] = array('#value' => '<span  
style="text-decoration: line-through;">' . t('delete') . '</span>');  
}  
}  
@@ -220,8 +226,10 @@ function supercron_firewall_form(&$form_  
}  
  
function supercron_firewall_add() {  
- - db_query("INSERT INTO {supercron_ips} (ip) VALUES ('%s')",  
$_POST['ip']);  
- - drupal_set_message("IP $_POST[ip] added.");  
+ if (preg_match('/\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/', $_POST['ip'])  
> 0) {  
+ db_query("INSERT INTO {supercron_ips} (ip) VALUES ('%s')",  
$_POST['ip']);  
+ drupal_set_message("IP $_POST[ip] added.");  
+ }  
}  
  
function supercron_firewall_enable() {  
@@ -457,7 +465,7 @@ function supercron_module_add_output($mo  
function supercron_output($id) {  
$module = db_fetch_array(db_query_range("SELECT * FROM  
{supercron_enabled_mods} WHERE id=%d", (int)$id, 0, 1));  
drupal_set_title(drupal_get_title() . $module["module_name"]);  
- - $output = $module["output"];  
+ $output = filter_admin_xss($module["output"]);  
return $output;  
}  
  
  
- --   
Justin Klein Keane  
http://www.MadIrish.net  
  
The digital signature on this e-mail may be confirmed using the  
PGP key located at: http://www.madirish.net/gpgkey  
-----BEGIN PGP SIGNATURE-----  
Version: GnuPG v1.4.11 (GNU/Linux)  
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/  
  
iPwEAQECAAYFAk7zYxMACgkQkSlsbLsN1gCl9gb+NQ2vIjvmR/ggbduVmzC1QGJk  
KZrtMbSpUStJvRj2pdZYRyfCCClQlSMR6nQwTa01+GNu7Hez7RTtSS8MwDENH5yW  
QU+DSY/yMrj4GKBRGUnT2W7bONAOSVjSeYJDTEQ1g5ORzBZNQi2M4iLv5qc6siJo  
nD+mQr8BbCqvAoxNwstmUIc+y9qrj9mXVKqyoPd1P9rC7EMbENWiqtp+29H4s4UF  
80A/zMcKLJ1H9Xu1ZX2BVPH+9816ZBk4U2sMLHr2cgySh41Dx/ADM20+8hAvyA9N  
V7gUil9RjhKbI0s6gmc=  
=YKEw  
-----END PGP SIGNATURE-----  
  
`