Microsoft Internet Explorer 'CStyleSheet' Uninitialized Memory Remote Code Execution Vulnerability

2010-03-24T00:00:00
ID SMNTC-40417
Type symantec
Reporter Symantec Security Response
Modified 2010-03-24T00:00:00

Description

Description

Microsoft Internet Explorer is prone to a remote code-execution vulnerability. Successful exploits will allow an attacker to run arbitrary code in the context of the user running the application. Failed attacks may cause denial-of-service conditions. NOTE: This issue was originally reported at the 2010 CanSecWest conference as part of the Pwn2Own contest. It was also previously documented in BID 38951 (Microsoft Internet Explorer Unspecified Remote Code Execution Vulnerabilities) but has been moved here to better document it.

Technologies Affected

  • Avaya Meeting Exchange - Client Registration Server
  • Avaya Meeting Exchange - Recording Server
  • Avaya Meeting Exchange - Streaming Server
  • Avaya Meeting Exchange - Web Conferencing Server
  • Avaya Meeting Exchange - Webportal
  • Avaya Messaging Application Server 4
  • Avaya Messaging Application Server 5
  • 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
  • Microsoft Internet Explorer 8

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 accept or execute files from untrusted or unknown sources.
Exercise caution when handling files received from unfamiliar or suspicious sources.

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 these issues 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.
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.

Updates are available to address this issue. Please see the references for more information.