Out-of-bounds memory write via heap overflow

Heap-based buffer overflow in gif2apng 1.9 allows attackers to write outside an allocated buffer via crafted GIF input. The main function miscalculates heap-buffer boundaries while processing attacker-controlled image data, permitting writes beyond the allocation with partial control over destination, contents, and length. Exploitation requires local execution and user interaction with a malicious GIF; impacts can include memory corruption, process crash, or code execution, but the record does not establish a specific exploit outcome.