Microsoft Internet Explorer Sandbox Bypass

Notification Type: IBM Security Protection Advisory
Notification Date: July 18, 2013
Notification Version: 1.0
Name: Microsoft Internet Explorer Sandbox Bypass
Public disclosure/
In the wild date:
July 09, 2013
Aliases: MS13-055
CVE: CVE-2013-4015

The Microsoft Internet Explorer sandbox (Protected Mode and Enhanced Protected Mode) has a vulnerability which allows code running in the sandbox to evade the elevation policy check which could result in privilege escalation.

Discoverer: This vulnerability was discovered and researched by Mark Yason of IBM X-Force.


ISS Coverage

Product Content Version
Network Protection XGS
Proventia Network IDS
Proventia Network IPS
Proventia MFS
Proventia Server (Linux)
RealSecure Network
RealSecure Server Sensor
Virtual Server Protection for VMware
Proventia Desktop
Proventia Server IPS (Windows)
Propagation Techniques ISS Protection Available

Remote exploit


*ADVISORY NOTE: Due to the nature of this vulnerability, IBM X-Force is not issuing any specific signature coverage on this advisory. We recommend applying the patch released by Microsoft for this issue.

Detailed Description

Business Impact:

In order to leverage this vulnerability, an attacker would first need to exploit a separate vulnerability that allows arbitrary code execution in the Internet Explorer sandbox. Exploitation of this vulnerability could result in privilege escalation, allowing code to be executed outside the Internet Explorer sandbox (Protected Mode and Enhanced Protected Mode) with the privileges of the currently logged on user.

*CVSS Base Score: 6.9
  Access Vector: Local
Access Complexity: Medium
Authentication: None
Confidentiality Impact: Complete
Integrity Impact: Complete
Availability Impact: Complete
Adjusted Temporal Score: 5.1
  Exploitability: Unproven
Remediation Level: Official-Fix
Report Confidence: Confirmed
Affected Products:

Internet Explorer 10 and earlier versions are affected. See References for details.

Technical Description:

The vulnerability exists because the Internet Explorer broker process extracts an incorrect application name from command lines containing certain characters supplied by the sandboxed process. Code running in the Internet Explorer sandbox can leverage this vulnerability to evade the elevation policy check in order to run any executable with an elevated privilege.


Refer to MS13-055 for patch, upgrade or suggested workaround information. See References.



Revision History

1.0 Initial publication.

* According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.
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