What is a buffer overflow?

A buffer overflow occurs when a program writes more data to a buffer than it can hold, exceeding the allocated memory space. This can lead to unexpected behavior, crashes, or vulnerabilities that attackers can exploit to run malicious code or gain unauthorized access to the system.

Overwriting adjacent memory can also result in data corruption and can affect the execution of other processes. It is a critical security concern, especially in systems programming where proper memory management is essential. Understanding buffer overflows is fundamental to writing secure code and implementing protective measures, such as input validation and proper memory handling techniques.