The (1) t1_parse_font_matrix function in type1/t1load.c, (2) cid_parse_font_matrix function in cid/cidload.c, (3) t42_parse_font_matrix function in type42/t42parse.c, and (4) ps_parser_load_field function in psaux/psobjs.c in FreeType before 2.5.4 do not check return values, which allows remote attackers to cause a denial of service (uninitialized memory access and application crash) or possibly have unspecified other impact via a crafted font.
https://savannah.nongnu.org/bugs/?41309
http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
http://www.openwall.com/lists/oss-security/2015/09/25/4
http://www.openwall.com/lists/oss-security/2015/09/11/4