Functional code that demonstrates an exploit of the Microsoft Internet Explorer use-after-free arbitrary code execution vulnerability is publicly available.
A vulnerability in Microsoft Internet Explorer could allow an unauthenticated, remote attacker to execute arbitrary code.
The vulnerability is due to improper memory operations when processing web content. An unauthenticated, remote attacker could exploit this vulnerability by convincing a targeted user to view a malicious website. A successful exploit could allow the attacker to execute arbitrary code on the targeted system with the privileges of the targeted user.
Functional code that exploits this vulnerability is available as part of the Metasploit framework.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
Microsoft Internet Explorer versions 6, 7, 8, 9, and 10 are affected when running on the following Microsoft products:
Windows XP SP3 and prior
Windows XP Professional x64 Edition SP2 and prior
Windows Server 2003 and x64 Edition SP2 and prior
Windows Server 2003 with SP2 and prior for Itanium-based Systems
Windows Vista and x64 Edition SP2 and prior
Windows Server 2008 for 32-bit and x64-based Systems SP2 and prior
Windows Server 2008 for Itanium-based Systems SP2 and prior
Windows 7 for 32-bit and x64-bit Systems SP1 and prior
Windows Server 2008 R2 for x64-based Systems SP1 and prior
Windows Server 2008 R2 for Itanium-based Systems SP1 and prior
Windows 8 for 32-bit and 64-bit Systems
Windows Server 2012
To exploit the vulnerability, the attacker may provide a link that directs a user to a malicious site 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 May 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 May 2013
Microsoft has released a security bulletin at the following link: MS13-037
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary code with the privileges of the user. If the user holds elevated privileges, the attacker could completely compromise the targeted system.
The vulnerability is due to an integer overflow error caused by improper handling of the dashstyle.array length for VML shapes by the vgx.dll module of the affected software.
An unauthenticated, remote attacker could exploit the vulnerability by convincing a user to view a malicious website using Internet Explorer. When processed, the site could cause a use-after-free error, resulting in memory corruption that the attacker could use to execute arbitrary code on the system with the privileges of the user.
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.
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.
Home Edition Base, SP1, SP2, SP3 | Professional Edition Base, SP1, SP2, SP3 | Professional x64 (AMD/EM64T) Base, SP2
for 32-bit systems Base | for x64-based systems Base
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