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Dotclear <= 2.6.2 (XML-RPC Interface) Authentication Bypass Vulnerability
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[-] Software Link:

http://dotclear.org/


[-] Affected Versions:

Version 2.6.2 and probably prior versions.


[-] Vulnerability Description:

The vulnerable code is located in the dcXmlRpc::setUser() method
(inc/core/class.dc.xmlrpc.php):

262.    /* Internal methods
263.    --------------------------------------------------- */
264.    private function setUser($user_id,$pwd)
265.    {
266.      if ($this->core->auth->userID() == $user_id) {
267.        return true;
268.      }
269.  
270.      if ($this->core->auth->checkUser($user_id,$pwd) !== true) {
271.        throw new Exception('Login error');
272.      }
273.  
274.      return true;

The vulnerability exists because of the method not properly verifying
the provided password
before being used in a call to the dcAuth::checkUser() method at line
270. This could be exploited
to bypass the authentication mechanism by sending an XML-RPC request
with a valid username and an
empty password. Successful exploitation of this vulnerability requires
the XML-RPC interface to
be enabled (disabled by default).


[-] Solution:

Update to version 2.6.3.


[-] Disclosure Timeline:

[14/05/2014] - Vendor notified
[15/05/2014] - Vendor response
[16/05/2014] - Version 2.6.3 released:
http://dotclear.org/blog/post/2014/05/16/Dotclear-2.6.3
[16/05/2014] - CVE number requested
[19/05/2014] - CVE number assigned
[21/05/2014] - Public disclosure


[-] CVE Reference:

The Common Vulnerabilities and Exposures project (cve.mitre.org)
has assigned the name CVE-2014-3781 to this vulnerability.


[-] Credits:

Vulnerability discovered by Egidio Romano.


[-] Original Advisory:

http://karmainsecurity.com/KIS-2014-05