Microsoft Outlook VEVENT Record Remote Code Execution Vulnerability

ID SMNTC-21931
Type symantec
Reporter Symantec Security Response
Modified 2007-01-09T00:00:00



Microsoft Outlook is prone to a remote code-execution vulnerability because the application fails to properly handle malformed iCal requests. A remote attacker can exploit this issue to execute arbitrary code with the privileges of unsuspecting users. A successful exploit may aid in the remote compromise of the underlying computer.

Technologies Affected

  • Microsoft Office 2000
  • Microsoft Office 2000 SP1
  • Microsoft Office 2000 SP2
  • Microsoft Office 2000 SP3
  • Microsoft Office 2003
  • Microsoft Office 2003 SP1
  • Microsoft Office 2003 SP2
  • Microsoft Office XP
  • Microsoft Office XP SP1
  • Microsoft Office XP SP2
  • Microsoft Office XP SP3
  • Microsoft Outlook 2000 SP2
  • Microsoft Outlook 2000 SR1
  • Microsoft Outlook 2000
  • Microsoft Outlook 2000 SP3
  • Microsoft Outlook 2002
  • Microsoft Outlook 2002 SP1
  • Microsoft Outlook 2002 SP2
  • Microsoft Outlook 2002 SP3
  • Microsoft Outlook 2003
  • Microsoft Outlook 2003 SP2


Run all software as a nonprivileged user with minimal access rights.
Running the affected Outlook client as a user with least privileges possible may help mitigate the impact of a successful attack.

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. Monitor logs regularly for any signs of unusual activity, such as repeated crashes.

Implement multiple redundant layers of security.
Memory-protection schemes (such as non-executable stack/heap configurations and randomly mapped memory segments) may complicate the successful exploit of memory-corruption vulnerabilities.

Do not open email messages from unknown or untrusted individuals.
Users should never trust incoming email messages originating from unknown or untrusted sources.

Microsoft has released an advisory and fixes to address this issue. Please see the references for more information.