ITS ADVISORY NUMBER:
2012-009

DATE(S) ISSUED:
02/14/2012

SUBJECT:
Cumulative Security Update for Internet Explorer (MS12-010)

OVERVIEW:

Multiple vulnerabilities have been discovered in Internet Explorer, Microsoft's web browser, which could allow an attacker to take complete control of an affected system. Successful exploitation of these vulnerabilities could result in an attacker gaining the same privileges as the logged on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

SYSTEMS AFFECTED:

• Internet Explorer 6
• Internet Explorer 7
• Internet Explorer 8
• Internet Explorer 9

RISK:
Government:

• Large and medium government entities: High
• Small government entities: High

Businesses:

• Large and medium business entities: High
• Small business entities: High

Home users: High

DESCRIPTION:
Four vulnerabilities have been discovered in Microsoft Internet Explorer. Details of these vulnerabilities are as follows:

Remote Code Execution Vulnerabilities 
Two remote code execution vulnerabilities have been discovered in Internet Explorer. These are memory corruption vulnerabilities that occur due to the way Internet Explorer accesses objects in memory that have not been properly deleted. These vulnerabilities may be exploited if a user visits a web page that is specifically crafted to take advantage of the vulnerabilities. Successful exploitation of any of these vulnerabilities could result in an attacker taking complete control of the system.

Information Disclosure Vulnerabilities 
Two information disclosure vulnerabilities have also been discovered in Internet Explorer. An attacker could successfully exploit the first vulnerability if a user visits a specially crafted website where they perform a copy operation and then pastes that information into a target website. Additionally, both vulnerabilities could be exploited if a user visits a specially crafted website which would allow the attacker to access information in other domains or Internet Explorer Zones. 

RECOMMENDATIONS:
We recommend the following actions be taken:

• Apply appropriate patches provided by Microsoft to vulnerable systems immediately after appropriate testing.
• Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
• Remind users not to open e-mail attachments from unknown users or suspicious e-mails from trusted sources.
• Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.

REFERENCES:
Microsoft:
http://technet.microsoft.com/en-us/security/bulletin/ms12-010

CVE:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0010
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0011
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0012
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0155