MS04-018 is not categorized as virus, worm, Trojan or backdoor. It is a critical vulnerability in Windows 2003/XP/2000/NT computers, known as MHTML URL Processing Vulnerability, which allows arbitrary code to be remotely executed in the vulnerable computer.
This vulnerability affects the following products:
- Microsoft Outlook Express 5.5.
- Microsoft Outlook Express 6.
If exploited successfully, MS04-018 allows hackers to gain remote control of the affected computer with the same privileges as the logged on user. If this user had administrator rights, the hacker could take complete control of the system: create, modify or delete files, install programs, create new user accounts, etc.
This vulnerability is exploited by creating a malicious web page and enticing users into accessing it. An e-mail message in HTML format could also be used.
If you have a Windows 2003/XP/2000/NT computer, it is recommendable to download and apply the security patch for this vulnerability available in the Microsoft Security bulletin MS04-018 or the latest cumulative update for Outlook Express.