Microsoft Internet Explorer HTML Objects 'substringData()' Remote Code Execution Vulnerability

Description

Microsoft Internet Explorer is prone to a remote code-execution vulnerability because it fails to perform adequate boundary checks when handling certain HTML object data. Attackers can leverage this issue to execute arbitrary code with the privileges of the user running the application. Successful exploits will compromise affected computers. Failed attacks may cause denial-of-service conditions.

Technologies Affected

• Avaya Messaging Application Server
• Avaya Messaging Application Server MM 1.1
• Avaya Messaging Application Server MM 2.0
• Avaya Messaging Application Server MM 3.0
• Avaya Messaging Application Server MM 3.1
• Microsoft Internet Explorer 6.0
• Microsoft Internet Explorer 6.0 SP1
• Microsoft Internet Explorer 7.0
• Nortel Networks CallPilot 1002rp
• Nortel Networks CallPilot 200i
• Nortel Networks CallPilot 201i
• Nortel Networks CallPilot 702t
• Nortel Networks CallPilot 703t
• Nortel Networks Centrex IP Client Manager 10.0
• Nortel Networks Centrex IP Client Manager 11.0
• Nortel Networks Centrex IP Client Manager 9.0

Recommendations

Run all software as a nonprivileged user with minimal access rights.
To limit the potential damage that successful exploits may achieve, run all nonadministrative software as an unprivileged user.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity. This includes but is not limited to requests that include NOP sleds and unexplained incoming and outgoing traffic. This may indicate exploit attempts or activity that results from successful exploits.

Do not follow links provided by unknown or untrusted sources.
Attackers can exploit this vulnerability by enticing a user to visit a malicious website. Do not follow links provided by sources of questionable integrity. Filtering HTML from emails may help remove a possible vector for transmitting malicious links to users.

Implement multiple redundant layers of security.
Various memory-protection schemes (such as nonexecutable and randomly mapped memory segments) may hinder an attacker’s ability to exploit this vulnerability to execute arbitrary code.

The vendor has released an advisory and fixes. Please see the references for more information.