When a programmer exploits written code that doesn't check for a defined amount of memory space they are executing which of the following attacks?

The correct answer to the following question will be "Buffer overflow".

Explanation:

For security policy and computing, the buffer overflow is a phenomenon where the code overwrites the boundaries of the buffer when adding data to the buffer and overwrites neighboring storage positions. A vulnerability of buffer overflow occurs when you offer so much data to a program. Excessive data corrupts memory space in the vicinity and it may change certain data. As a consequence, the program could report a mistake or act differently. These vulnerabilities are often referred to as buffer overrun. If the programmer constructs a compiled code which does not test for a given quantity of system memory, the buffer overflow would strike on it.

Therefore, Buffer overflow is the right answer.