DOS Attacks Denial Of Service Freezing X-Windows (Linux) If the host accepts a telnet session to the X-Window port you can freeze it up by making multiple connections. port = (6000-6025) Disable Accounts Some systems disable an account after X number of bad logins, or waits X seconds. You can use this feature to lock out specific users from the system. Linux & TCP Time Inetd under Linux is known to crash if to many SYN packets sends to daytime (port 13) and/or time (port 37). Disable Services Some Unix Systems will disable a service after X sessions have been open in a specific time. Most have the default set to something reasonible like (1000-1200) but not all, some SunOS systems Have it set low like (30-40). Novells Netware FTP Novell Netwares FTP server will crash if it has multiple people connect to it at once or many in a short amount of time. ICMP Attacks Since Gateways use ICMP redirect to override routing tables, you can use it to send a route that loses it connectivity or send false messages to the host. (hint: you need to know of an existin connection) or you can send spoofed ICMP Source Quench messages, which can slow down the conncection. False Messages to Send Destination Unreachable Parameter Problem Packet Too Big Time to Live Exceeded These will all reset the connection. Email Bombing This is a lamerish activity. It is used by sending a large amount of mail to a specific address thust using up bandwith. Crashing Systems with Ping From Window 95 Machines If some one can ping your machine from a windows 95 machine he ot she can freeze, reboot, or crash your machine. The code is posted below. ping -l 65510 address.to.the.machine -=DHC Demonic Hacking Clan=- Authored By Roke¤ http://www.dhc.hactivist.net Roke@dhc.8m.com 1:22PM 8/22/99