Sams Teach Yourself TCP/IP in 24 Hours, Third Edition

Other Access Techniques

Password access isn't the only way to gain entry to a system. The following sections discuss some other common access techniques, including

• Buffer overflow

• Script tricks

• Session hijacking

• Email worms

Buffer Overflow

When a computer receives data over a network connection (or for that matter, even when it receives data from a keyboard), the computer must reserve enough memory space to receive the complete data set. This reception space is called a buffer. Network computer applications must provide a buffer to receive input. If user input overflows the buffer, strange things happen. If the input is not properly managed, the data that overflows the buffer can become resident in the CPU's execution area, which means that commands ...