FreeType: Heap-based buffer overflow by processing FontType42 fonts with negative length of SFNT strings (FT bug #30656)

Array index error in the t42parsesfnts function in type42/t42parse.c in FreeType before 2.4.2 allows remote attackers to cause a denial of service application crash or possibly execute arbitrary code via negative size values for certain strings in FontType42 font files, leading to a heap-based...