Vulnerability protection

A vulnerability in Internet Explorer (IE) could, upon successful exploitation, allow a remote attacker to execute arbitrary code in the context of the current user within IE.

Microsoft has reported about a remote code execution vulnerability in Internet Explorer (IE). The vulnerability exists when IE accesses a deleted or an improperly allocated object in memory, causing a memory corruption condition that may allow code execution in the context of a current user.

To mitigate the impact of this vulnerability, users are advised to implement some workarounds such as applying the relevant Microsoft Fix it solution ("CVE-2013-3893 MSHTML Shim Workaround"), or deploying the Enhanced Mitigation Experience Toolkit (EMET). Complete instruction is available from Microsoft Security Advisory (2887505).

F-Secure detects the files taking advantage of this vulnerability with two detections:

1. Exploit:HTML/CVE-2013-3893.A - starting in Hydra database version 2013-09-20_06, which was released on 20 September 2013
2. JS:Exploit.CVE-2013-3893.A - starting in Aquarius database version 2013-09-20_05, which was released on 20 September 2013

Please allow F-Secure products to block installation of files that take advantage of this vulnerability.

CVE-2013-3893

Microsoft recommends users to apply the following workarounds to mitigate the impact of the vulnerability until a patch is released:

• Apply the Microsoft Fix it solution, "CVE-2013-3893 MSHTML Shim Workaround"
• Deploy the Enhanced Mitigation Experience Toolkit (EMET)
• Set Internet security zone setting to "High"
• Configure Internet Explorer to prompt before running Active Scripting, or disable Active Scripting 

For complete instructions, please refer to Microsoft Security Advisory (2887505).

Removal/Disinfection
Allow F-Secure Internet Security or F-Secure Anti-Virus to block installation of malicious files, and to remove or disinfect malicious files if found on the system.

Microsoft Security Advisory (2887505)

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