Microsoft NetMeeting with Remote Desktop Sharing enabled allows remote attackers to cause a denial of service (CPU utilization) via a sequence of null bytes to the NetMeeting port, aka the "NetMeeting Desktop Sharing" vulnerability.
https://exchange.xforce.ibmcloud.com/vulnerabilities/5368
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2000/ms00-077
http://www.securityfocus.com/archive/1/140341
http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ273854