Heap-based buffer overflow in the zzip_mem_entry_extra_block function in memdisk.c in zziplib 0.13.62, 0.13.61, 0.13.60, 0.13.59, 0.13.58, 0.13.57, 0.13.56 allows remote attackers to cause a denial of service (crash) via a crafted ZIP file.