MS-ISAC ADVISORY NUMBER:
2008-027

DATE(S) ISSUED:
8/12/2008

SUBJECT:
Vulnerabilities in Internet Explorer Could Allow Remote Code Execution

OVERVIEW:

Six vulnerabilities have been discovered in Microsoft Internet Explorer that could allow an attacker to take complete control of an affected system. These vulnerabilities may be exploited if a user visits a specifically crafted web page. Successful exploitation will result in an attacker gaining the same privileges as the logged on user. If the user is logged in with administrator privileges, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Failed exploit attempts will result in a denial-of-service condition.

SYSTEMS AFFECTED:

  • Microsoft Internet Explorer 5.01
  • Microsoft Internet Explorer 6
  • Microsoft Internet Explorer 7

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:
Six vulnerabilities have been discovered in Microsoft Internet Explorer that could allow an attacker to take complete control of an affected system. Details of these vulnerabilities are as follows:

HTML Objects Memory Corruption Vulnerability
Four remote code vulnerabilities have been discovered in the way Internet Explorer handles unexpected calls to certain HTML objects. This can result in memory corruption on the affected system.

Unitialized Memory Corruption Vulnerability
A remote code vulnerability has been discovered in the way Internet Explorer accesses memory. Specifically, the vulnerability is caused by Internet Explorer attempting to access objects that have not been initialized or have been deleted.

HTML Component Handling Vulnerability
A remote code vulnerability has been discovered in the print-preview function of Internet Explorer. Internet Explorer fails to perform sufficient input validation on certain parameters when processing these requests.

All of these vulnerabilities can be exploited by an attacker if a user visits a specially crafted malicious web site. Successful exploitation could allow an attacker to execute arbitrary code on the affected system. If the user is logged in with administrator privileges, the attacker could then install programs; view, change, or delete data; or create new accounts with full privileges.

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.
  • Do not visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Read all e-mail messages in plain text.

REFERENCES:
Microsoft:
http://www.microsoft.com/technet/security/bulletin/MS08-045.mspx(New Window)

Security Focus:
http://www.securityfocus.com/bid/28295/(New Window)

CVE:
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2254(New Window)
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2255(New Window)
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2256(New Window)
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2257(New Window)
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2258(New Window)
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-2259(New Window)


This cyber advisory was issued by the Multi-State Information Sharing and Analysis Center (MS-ISAC) and was intended for government entities. The information may or may not be applicable to the general public and accordingly, the MS-ISAC does not warrant its use for any specific purposes.