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Microsoft Internet Explorer 8 CMarkup use-after-free vulnerability

Vulnerability Note VU#239151

Original Release Date: 2014-05-21 | Last Revised: 2014-05-23


Microsoft Internet Explorer 8 contains a use-after-free vulnerability that can allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.


Microsoft Internet Explorer 8 contains a use-after-free vulnerability. This can allow for arbitrary code execution. Additional details may be found in the Zero Day Initiative advisory ZDI-14-140.


By convincing a user to view a specially crafted HTML document (e.g., a web page or an HTML email message or attachment), an attacker may be able to execute arbitrary code.


Apply an Update

Users should upgrade to Internet Explorer 11.

Users that are unable to upgrade past Internet Explorer 8 should consider the following workarounds. Windows XP users will not be able to upgrade past Internet Explorer 8.

Use the Microsoft Enhanced Mitigation Experience Toolkit

The Microsoft Enhanced Mitigation Experience Toolkit (EMET) can be used to help prevent exploitation of this vulnerability. Note that platforms that do not support ASLR, such as Windows XP and Windows Server 2003, will not receive the same level of protection that modern Windows platforms will.

Disable ActiveX and Active Scripting

Set the Internet security zone setting to "High" to block ActiveX Controls and Active Scripting.

Vendor Information


Microsoft Corporation Affected

Updated:  May 21, 2014



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

CVSS Metrics

Group Score Vector
Base 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P
Temporal 6.5 E:H/RL:W/RC:C
Environmental 8.2 CDP:MH/TD:H/CR:H/IR:H/AR:L



This vulnerability was discovered by Peter 'corelanc0d3r' Van Eeckhoutte and coordinated by the Zero Day Initiative.

This document was written by Jared Allar.

Other Information

CVE IDs: CVE-2014-1770
Date Public: 2014-05-21
Date First Published: 2014-05-21
Date Last Updated: 2014-05-23 16:39 UTC
Document Revision: 12

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