The LZW decompressor in (1) the BufCompressedFill function in fontfile/decompress.c in X.Org libXfont before 1.4.4 and (2) compress/compress.c in 4.3BSD, as used in zopen.c in OpenBSD before 3.8, FreeBSD, NetBSD 4.0.x and 5.0.x before 5.0.3 and 5.1.x before 5.1.1, FreeType 2.1.9, and other products, does not properly handle code words that are absent from the decompression table when encountered, which allows context-dependent attackers to trigger an infinite loop or a heap-based buffer overflow, and possibly execute arbitrary code, via a crafted compressed stream, a related issue to CVE-2006-1168 and CVE-2011-2896.

The LZW decompressor in the LWZReadByte function in giftoppm.c in the David Koblas GIF decoder in PBMPLUS, as used in the gif_read_lzw function in filter/image-gif.c in CUPS before 1.4.7, the LZWReadByte function in plug-ins/common/file-gif-load.c in GIMP 2.6.11 and earlier, the LZWReadByte function in img/gifread.c in XPCE in SWI-Prolog 5.10.4 and earlier, and other products, does not properly handle code words that are absent from the decompression table when encountered, which allows remote attackers to trigger an infinite loop or a heap-based buffer overflow, and possibly execute arbitrary code, via a crafted compressed stream, a related issue to CVE-2006-1168 and CVE-2011-2895.

The decompress function in compress42.c in (1) ncompress 4.2.4 and (2) liblzw allows remote attackers to cause a denial of service (crash), and possibly execute arbitrary code, via crafted data that leads to a buffer underflow.