Valve Steam Client Application 1559/1559 – Local Privilege Escalation
Valve Steam Client Application v1559/1559 Local Privilege Escalation Vendor: Valve Corporation Product web page: http://www.steampowered.com Affected version: Built: Jun 1, 2011 at 15:31:24 Steam API: v010 Steam package versions 1559 / 1559 File version: 1.0.968.628 Summary: Steam is a digital distribution, digital rights management, multiplayer and communications platform developed by Valve Corporation. It is used to distribute games and related media online, from small independent developers to larger software houses. Steam also has community features, automated game updates, and in-game voice and chat functionality. Desc: Steam is vulnerable to 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 Control) for the "Users" group, for the binary file Steam.exe, GameOverlayUI.exe and steamerrorreporter.exe. The binary (Steam.exe) is set by default to Startup with "-silent" parameter. Tested on: Microsoft Windows XP Professional SP3 (EN) Vendor status: 24.06.2011 - Vulnerability discovered. 25.06.2011 - Initial contact with the vendor. 25.06.2011 - Auto-reply from the vendor stating that the message is received. 28.06.2011 - No reply from the vendor. 29.06.2011 - Public security advisory released. Vulnerability discovered by Gjoko 'LiquidWorm' Krstic liquidworm gmail com Advisory ID: ZSL-2011-5022 Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2011-5022.php 24.06.2011 ------------------------------------------------------------ C:\Program Files\Steam>cacls Steam.exe C:\Program Files\Steam\Steam.exe BUILTIN\Users:F <--- NT AUTHORITY\SYSTEM:F BUILTIN\Power Users:C BUILTIN\Administrators:F LABPC\User101:F |