This update for pngcheck fixes the following issues:
pngcheck was updated to 3.0.3:
Version 3.0.1:
fixed a crash bug (and probable vulnerability) in large (MNG) LOOP chunks
Version 3.0.2:
fixed a divide-by-zero crash bug (and probable vulnerability)
in interlaced images with extra compressed data beyond the
nominal end of the image data (found by 'chiba of topsec alpha
lab')