Buffer Overflow Causes. ©2002, Jedidiah R. Crandall, Susan L. Gerhart, Jan G. Hogle.  http://sfsecurity.pr.erau.edu
Types of buffer overflow attacks
Stack smashing or heap-based attacks
The attacker can hijack execution of the program, and if the program was running with elevated privileges, the attacker now has those privileges
This is the way many worms spread by tricking a network server into running the a program the attacker wrote
Data corruption
An attacker can change their privileges or other security-related data by overwriting it in memory
Program crash
A program crash can lead to denial-of-service because the service that program was providing will not be there until the program is restarted
Sometimes a program crash causes a “core dump” where the entire memory of the program (possibly security-sensitive data) is written out to a file the attacker may be able to read