The tt_cmap4_validate function in sfnt/ttcmap.c in FreeType before 2.5.4 validates a certain length field before that field's value is completely calculated, which allows remote attackers to cause a denial of service (out-of-bounds read) or possibly have unspecified other impact via a crafted cmap SFNT table. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-9663
