The read_boot function in boot.c in dosfstools before 4.0 allows attackers to cause a denial of service (crash) via a crafted filesystem, which triggers a heap-based buffer overflow in the (1) read_fat function or an out-of-bounds heap read in (2) get_fat function. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-4804