Functional code that exploits the Microsoft Internet Explorer SLayoutRun use-after-free arbitrary code execution vulnerability is publicly available.
Description
Microsoft Internet Explorer contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system with the privileges of the user.
The vulnerability is due to improper memory operations when processing malicious HTML content. An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to view a malicious website. If successful, the attacker could execute arbitrary code on the system with the privileges of the user.
Functional code that exploits this vulnerability is publicly available.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
Warning Indicators
Microsoft Internet Explorer version 8 is vulnerable when running on the following Microsoft systems:
Windows XP SP3
Windows XP Professional x64 Edition SP2
Windows Server 2003 SP2
Windows Server 2003 x64 Edition SP2
Windows Vista SP2
Windows Vista x64 Edition SP2
Windows Server 2008 for 32-bit Systems SP2
Windows Server 2008 for x64-based Systems SP2
Windows Server 2008 R2 for x64-based Systems SP1 and prior
Windows Server 2008 R2 for Itanium-based Systems SP1 and prior
Windows 7 for 32-bit Systems SP1 and prior
Windows 7 for x64-based Systems SP1 and prior
IntelliShield Analysis
To exploit the vulnerability, the attacker may provide a link that directs a user to a malicious website and use misleading language or instructions to persuade the user to follow the provided link.
The Cisco Applied Intelligence team has created an Applied Mitigation Bulletin to address vulnerabilities that Microsoft disclosed in the February 2013 security bulletin release. This Cisco bulletin, which assists administrators in identifying or mitigating these vulnerabilities using Cisco devices, is available at the following link: Cisco Applied Mitigation Bulletin: Microsoft Security Bulletin Release for February 2013
Vendor Announcements
Microsoft has released a security bulletin at the following link: MS13-009
Impact
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary code on a targeted system with the privileges of the user. If the user holds elevated privileges, the attacker could execute code that results in a complete system compromise.
Technical Information
The vulnerability is due to improper memory operations when processing malicious HTML content in Internet Explorer. The affected application could release a CParaElement node, but a reference is kept in CDoc. This reference can be reused when a CDoc relayout is performed. This action results in a use-after-free error that could corrupt memory.
An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to view a malicious website. Processing the malicious data could trigger a memory corruption condition that the attacker could use to execute arbitrary code on the system with the privileges of the user.
Safeguards
Administrators are advised to apply the appropriate updates.
Administrators may consider configuring Internet Explorer to prompt users before running Active Scripting or ActiveX controls by setting the Internet and Local Intranet security zone settings to High. Alternately, administrators could disable Active Scripting and ActiveX controls in these security zones.
Users are advised not to open e-mail messages from suspicious or unrecognized sources. If users cannot verify that links or attachments included in e-mail messages are safe, they are advised not to open them.
Administrators may consider using the Microsoft Baseline Security Analyzer (MBSA) scan tool to identify common security misconfigurations and missing security updates on system endpoints.
Administrators are advised to monitor affected systems.
Patches/Software
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Microsoft Update service. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
Signatures
Cisco Systems Cisco Intrusion Prevention System (IPS) 6.0
Version 1, February 12, 2013, 1:43 PM: Microsoft Internet Explorer contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system. Updates are available.
Datacenter Edition SP2 | Datacenter Edition, 64-bit SP2 | Enterprise Edition SP2 | Enterprise Edition, 64-bit SP2 | Essential Business Server Premium SP2 | Essential Business Server Premium, 64-bit SP2 | Essential Business Server Standard SP2 | Standard Edition SP2 | Standard Edition, 64-bit SP2 | Web Server SP2 | Web Server, 64-bit SP2
Microsoft, Inc.
Windows Server 2008 R2
Itanium-Based Systems Edition Base, SP1 | x64-Based Systems Edition Base, SP1
Microsoft, Inc.
Windows Vista
Business SP2 | Business x64 Edition SP2 | Enterprise SP2 | Enterprise x64 Edition SP2 | Home Basic SP2 | Home Basic x64 Edition SP2 | Home Premium SP2 | Home Premium x64 Edition SP2 | Ultimate SP2 | Ultimate x64 Edition SP2
Microsoft, Inc.
Windows XP
Home Edition SP3 | Media Center Edition SP3 | Professional Edition SP3 | Professional x64 (AMD/EM64T) SP2 | Tablet PC Edition SP3
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