Ubisoft Uplay 4.6 Insecure File Permissions Local Privilege Escalation Vendor: Ubisoft Entertainment S.A. Product web page: http://www.ubi.com Affected version: 4.6.3208 (PC) 4.5.2.3010 (PC) Summary: Uplay is a digital distribution, digital rights management, multiplayer and communications service created by Ubisoft to provide an experience similar to the achievements/trophies offered by various other game companies. - Uplay PC is a desktop client which replaces individual game launchers previously used for Ubisoft games. With Uplay PC, you have all your Uplay enabled games and Uplay services in the same place and you get access to a whole new set of features for your PC games. Desc: Uplay for PC suffers from an elevation of privileges vulnerability which can be used by a simple user that can change the executable file with a binary of choice. The vulnerability exist due to the improper permissions, with the 'F' flag (Full) for 'Everyone' group, making the entire directory 'Ubisoft Game Launcher' and its files and sub-dirs world-writable. Tested on: Microsoft Windows 7 Professional SP1 (EN) Microsoft Windows 7 Ultimate SP1 (EN) Vulnerability discovered by Gjoko 'LiquidWorm' Krstic @zeroscience Advisory ID: ZSL-2014-5191 Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2014-5191.php Vendor: http://forums.ubi.com/forumdisplay.php/513-Uplay 30.05.2014 -- ======================================================================= C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher>icacls *.exe |findstr Everyone UbisoftGameLauncher.exe Everyone:(I)(F) UbisoftGameLauncher64.exe Everyone:(I)(F) Uninstall.exe Everyone:(I)(F) Uplay.exe Everyone:(I)(F) UplayCrashReporter.exe Everyone:(I)(F) UplayService.exe Everyone:(I)(F) C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher> ======================================================================= C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher>icacls Uplay.exe Uplay.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) BUILTIN\Users:(I)(RX) Successfully processed 1 files; Failed processing 0 files C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher> ======================================================================= C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher>icacls *.exe |findstr (F) UbisoftGameLauncher.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) UbisoftGameLauncher64.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) Uninstall.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) Uplay.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) UplayCrashReporter.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) UplayService.exe Everyone:(I)(F) NT AUTHORITY\SYSTEM:(I)(F) BUILTIN\Administrators:(I)(F) C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher> ======================================================================= C:\Program Files (x86)\Ubisoft>icacls "Ubisoft Game Launcher" Ubisoft Game Launcher Everyone:(OI)(CI)(F) NT SERVICE\TrustedInstaller:(I)(F) NT SERVICE\TrustedInstaller:(I)(CI)(IO)(F) NT AUTHORITY\SYSTEM:(I)(F) NT AUTHORITY\SYSTEM:(I)(OI)(CI)(IO)(F) BUILTIN\Administrators:(I)(F) BUILTIN\Administrators:(I)(OI)(CI)(IO)(F) BUILTIN\Users:(I)(RX) BUILTIN\Users:(I)(OI)(CI)(IO)(GR,GE) CREATOR OWNER:(I)(OI)(CI)(IO)(F) Successfully processed 1 files; Failed processing 0 files C:\Program Files (x86)\Ubisoft> ======================================================================= ======================================================================= Changed permissions (vendor fix): --------------------------------- C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher>cacls Uplay.exe C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\Uplay.exe BUILTIN\Users:(ID)(special access:) DELETE READ_CONTROL WRITE_DAC WRITE_OWNER STANDARD_RIGHTS_REQUIRED FILE_READ_DATA FILE_WRITE_DATA FILE_APPEND_DATA FILE_READ_EA FILE_WRITE_EA FILE_EXECUTE NT AUTHORITY\SYSTEM:(ID)F BUILTIN\Administrators:(ID)F BUILTIN\Users:(ID)R labpc\user4dmin:(ID)F C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher> =======================================================================