Microsoft Internet Explorer (CVE-2009-1141) Uninitialized Memory Remote Code Execution Vulnerability

Description

Microsoft Internet Explorer is prone to a remote code-execution vulnerability. Attackers can exploit this issue to execute arbitrary code in the context of the user running the application. Successful exploits will compromise the application and possibly the computer. 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
• Nortel Networks CallPilot 1002rp
• Nortel Networks CallPilot 1005r
• Nortel Networks CallPilot 200i
• Nortel Networks CallPilot 201i
• Nortel Networks CallPilot 702t
• Nortel Networks Contact Center Manager Server
• Nortel Networks Contact Center NCC
• Nortel Networks Multimedia Comm Mas
• Nortel Networks Self-Service MPS 100
• Nortel Networks Self-Service MPS 1000
• Nortel Networks Self-Service MPS 500
• Nortel Networks Self-Service Peri Application
• Nortel Networks Self-Service Peri NT Server
• Nortel Networks Self-Service Peri Workstation

Recommendations

Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, always run nonadministrative software as an unprivileged user with minimal access rights.

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.
Web users should be cautious about following links to sites that are provided by unfamiliar or suspicious sources. Filtering HTML from emails may help remove a possible vector for transmitting malicious links to users.

Set web browser security to disable the execution of script code or active content.
Since a successful exploit of this issue requires malicious code to execute in web clients, consider disabling support for script code and active content within the client browser. Note that this mitigation tactic might adversely affect legitimate websites that rely on the execution of browser-based script code.

Implement multiple redundant layers of security.
Memory-protection schemes (such as nonexecutable stack and heap configurations and randomly mapped memory segments) will complicate exploits of memory-corruption vulnerabilities.

The vendor has released an advisory along with fixes. Please see the references for details.