Corrupting program memory via malicious input data is known as a code-execution attack, not a data-only attack. The fuzzed program crashes because its executable code got overwritten directly by the input, or it got overwritten indirectly by the logic when it tries to process bad data. An exploit involves injecting external code, or overwriting memory addresses to change the original logic flow to do something else.

A data-only attack would be an attack that reuses the original logic by only corrupting data inputs (such as a file path), without injecting code or changing logic.