When you execute a program on the computer, the data temporarily stays in the buffer. What happens if the filled data exceeds the capacity of the buffer? Overflow data will overwrite legal data, just like a glass of water overflows a cup. This paper will reveal the principle and countermeasures of buffer overflow to help readers better protect digital assets.

Buffer overflow principle

Buffer overflow means that the filled data exceeds the capacity of the buffer, resulting in the overflow data overwriting legal data. In this case, the program may crash and even the operating system may be affected.

Programming error

The root cause of buffer overflow is programming error. Problems occur when the buffer is full and the program does not check the boundary or stop receiving data. Programmers used to ignore this check because of limited resources, but now the situation has changed.

Security threat of buffer overflow

Buffer overflow may cause serious security threats. If malicious data covers the buffer, it may become the intrusion code of "hacker" or virus, which will lead to the attack of computer system.

Coping Strategies for Buffer Overflow

In order to deal with buffer overflow, we can use data redundancy technology, such as mirror storage, to protect key data. By backing up and storing data copies, we can still recover the original data even if some data is overwritten or damaged.