KissFFT Integer Overflow Heap Buffer Overflow via kiss_fftndr_alloc()

Summary

KissFFT before commit 8a8e66e contains an integer overflow vulnerability in the kiss_fftndr_alloc() function in kiss_fftndr.c where the allocation size calculation dimOther*(dimReal+2)*sizeof(kiss_fft_scalar) overflows signed 32-bit integer arithmetic before being widened to size_t, causing malloc() to allocate an undersized buffer. Attackers can trigger heap buffer overflow by providing crafted dimensions that cause the multiplication to exceed INT_MAX, allowing writes beyond the allocated buffer region when kiss_fftndr() processes the data.