Buffer overflow in the progressive reader for libpng 1.2.x before 1.2.4, and 1.0.x before 1.0.14, allows attackers to cause a denial of service (crash) via a PNG data stream that has more IDAT data than indicated by the IHDR chunk.
http://www.linux-mandrake.com/en/security/2002/MDKSA-2002-049.php
http://www.debian.org/security/2002/dsa-140
http://rhn.redhat.com/errata/RHSA-2002-152.html
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000512