McAfee VirusScan Enterprise 8.8 Security Bypass
Posted on 05 March 2016
Security Advisory @ Mediaservice.net Srl (#01, 13/04/2016) Data Security Division Title: McAfee VirusScan Enterprise security restrictions bypass Application: McAfee VirusScan Enterprise 8.8 and prior versions Platform: Microsoft Windows Description: A local Windows administrator is able to bypass the security restrictions and disable the antivirus engine without knowing the correct management password Author: Maurizio Agazzini <inode@mediaservice.net> Vendor Status: Fixed References: http://lab.mediaservice.net/advisory/2016-01-mcafee.txt http://lab.mediaservice.net/code/mcafee_unprotector.c 1. Abstract. McAfee VirusScan Enterprise has a feature to protect the scan engine from local Windows administrators. A management password is needed to disable it, unless Windows is running in "Safe Mode". >From our understanding this feature is implemented insecurely: the McAfee VirusScan Console checks the password and requests the engine to unlock the safe registry keys. No checks are done by the engine itself, so anyone can directly request the engine to stop without knowing the correct management password. 2. Example Attack Session. The attack can be reproduced in different ways, here are some examples. Example 1: Open the McAfee VirusScan Console and Sysinternals Process Explorer. Under Process Explorer: - Locate the mcconsol.exe process - Type CTRL+L (show lower pane) - Search for all "HKLMSOFTWAREMcAfeeDesktopProtection" keys - Close all the handles of this registry key Go back to the McAfee Console and: - Go to: Tools -> General Options - Select the "Password Options" tab - Select "No password" and apply settings Now it is possible to stop the antivirus engine. Example 2: A specific tool has been written to request to disable password protection. After running the tool you can disable it via the VirusScan Console. Code: http://lab.mediaservice.net/code/mcafee_unprotector.c 3. Affected Platforms. All McAfee Viruscan Enterprise versions prior to 8.8 without SB10151 are affected. Exploitation of this vulnerability requires that an attacker has local Windows administrator privileges. 4. Fix. On 25 February 2016, version SB10151 hotfix has been relased by McAfee, which fixes the described vulnerability. https://kc.mcafee.com/corporate/index?page=content&id=SB10151 5. Proof Of Concept. See Example Attack Session above. 6. Timeline 07/11/2014 - First communication sent to McAfee 17/11/2014 - Second communication sent to McAfee 17/11/2014 - McAfee: Request to send again vulnerability information 18/11/2014 - Sent vulnerability information and PoC again 11/12/2014 - McAfee: Problem confirmed 09/03/2015 - Request for update to McAfee 06/05/2015 - Request for update to McAfee 06/05/2015 - McAfee: Patch release planned for Q3 20/08/2015 - McAfee: Request for deadline delay (31/03/2016) 25/02/2016 - McAfee: SB10151 patch has been relased Copyright (c) 2014-2016 @ Mediaservice.net Srl. All rights reserved. -- Maurizio Agazzini CISSP, CSSLP, OPST Senior Security Advisor @ Mediaservice.net Srl Tel: +39-011-32.72.100 Via Santorelli, 15 Fax: +39-011-32.46.497 10095 Grugliasco (TO) ITALY http://mediaservice.net/disclaimer "C programmers never die. They are just cast into void"
