|The png_decompress_chunk function in pngrutil.c in libpng 1.0.x before
1.0.53, 1.2.x before 1.2.43, and 1.4.x before 1.4.1 does not properly
handle compressed ancillary-chunk data that has a disproportionately
large uncompressed representation, which allows remote attackers to
cause a denial of service (memory and CPU consumption, and application
hang) via a crafted PNG file, as demonstrated by use of the deflate
compression method on data composed of many occurrences of the same
character, related to a "decompression bomb" attack.