The (1) putcontig8bitYCbCr21tile function in tif_getimage.c or (2) NeXTDecode function in tif_next.c in LibTIFF allows remote attackers to cause a denial of service (uninitialized memory access) via a crafted TIFF image, as demonstrated by libtiff-cvs-1.tif and libtiff-cvs-2.tif.