Microsoft Malformed IPX NMPI Packet Vulnerability Patch for Windows 98 and 98 Second Edition eliminates a security vulnerability which could be used to cause your system to fail, and depending on the number of affected machines on a network, potentially flood it with superfluous data. This is a denial of service attack. A malicious user could use this vulnerability to cause an affected machine to fail and possibly cause a broadcast storm on the network. The chief limitation of this vulnerability is that the affected system component is not installed by default, and even if it were, the vulnerability could only be exploited in restricted circumstances. In a corporate setting, it can only be exploited by a user who can log onto the network. In a home setting, it can only be exploited if the machine is connected to the Internet via a cable modem or DSL connection, and the malicious user was on the same network segment as the affected machine.