Dotclear <= 2.6.2 (XML-RPC Interface) Authentication Bypass Vulnerability

• 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):

	private function setUser($user_id,$pwd)
	{
		if ($this->core->auth->userID() == $user_id) {
			return true;
		}

		if ($this->core->auth->checkUser($user_id,$pwd) !== true) {
			throw new Exception('Login error');
		}

		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.