0-Day Fixes

Internet Explorer remote code execution vulnerability

Report ID: MAPP-CVE20133893
Date Published: 20 September 2013
Date Revised: 9 October 2013
Criticality: Critical
Compromise Type: remote-code-execution
Compromise From: remote
Affected Product/Component:
Internet Explorer 6
Internet Explorer 7
Internet Explorer 8
Internet Explorer 9
Internet Explorer 10
Internet Explorer 11


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.

Detailed Description

UPDATE: The patch for this vulnerability was released on 9 October 2013, as detailed in: Internet Explorer cumulative security update.

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 Reference

  • CVE-2013-3893

Detected Exploit

  • Exploit:HTML/CVE-2013-3893.A
  • JS:Exploit.CVE-2013-3893.A
  • Hydra database version 2013-09-20_06 at 08:01:32 UTC
  • Aquarius database version 2013-09-20_05 at 09:07:45 UTC
Release Dates
  • 20 September 2013


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).


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.

Original Source

Microsoft Security Advisory (2887505)