Check Point IPS Provides Protection Against Four Microsoft Internet Explorer Vulnerabilities
( Microsoft Security Bulletin MS11-057 )
Summary
Four vulnerabilities in Internet Explorer have been disclosed by Microsoft — one ranked Critical in severity, and three ranked High. Successful exploitation of three of these issues can result in remote execution of arbitrary code on the system under attack, while the forth can allow an attacker to access and view content that is outside his own domain or IE zone.
Details
A memory corruption vulnerability in Internet Explorer (CVE-2011-1964) occurs when it tries to access uninitialized or deleted objects. By convincing a user to open a specially crafted web page that leverages this flaw, an attacker can execute malicious code on the targeted system.
A race condition issue (CVE-2011-1257) can be created when Internet Explorer attempts to process a malicious script, which can cause IE to crash in a way that then allows an attacker to execute malicious code on the targeted system.
A flaw (CVE-2011-1961) in the way Internet Explorer's URI handler validates telnet commands can be exploited by convincing a user to open a malicious web page, thereby enabling the attacker to execute malicious code on the affected system.
An information disclosure vulnerability (CVE-2011-1960) is due to a flaw in Internet Explorer that allows it to be exploited during certain internal processes via specially crafted web pages, allowing an attacker to access and view information on a domain or IE zone that is not his own.
Affected Products and Solution
Check Point recommends applying the Cumulative Security Update for Internet Explorer as detailed in the MS11-057 bulletin. In the meantime, the Check Point IPS Software Blade provides immediate network protection for unpatched systems against all of these issues in the latest IPS update by detecting and blocking attempts to exploit them. The following table lists each vulnerability with its severity as well as the affected Internet Explorer versions, associated CVE reference, and Check Point Protection.
| Internet Explorer Vulnerability | Severity | Affected Internet Explorer Versions | Industry Reference | Check Point Protection |
|---|---|---|---|---|
| Style Object Memory Corruption | Critical | 6, 7, 8, 9 | CVE-2011-1964 | CPAI-2011-359 |
| Window Open Race Condition | High | 6, 7, 8 | CVE-2011-1257 | CPAI-2011-358 |
| Telnet Handler RCE | High | 6, 7, 8, 9 | CVE-2011-1961 | CPAI-2011-356 |
| Cross Domain Information Disclosure | High | 6, 7, 8, 9 | CVE-2011-1960 | CPAI-2011-357 |
Originally Published:
Last Updated: 09-Aug-2011