Debian 3.0: DSA-140-1 Important: Buffer Overflow in Libpng Package

Developers of the PNG library have fixed a buffer overflow in the
progressive reader when the PNG datastream contains more IDAT data
than indicated by the IHDR chunk. Such deliberately malformed
datastreams would crash applications which could potentially allow an
attacker to execute malicious code. Programs such as Galeon,
Konquerer and various others make use of these libraries.

To find out which packages depend on this library, you may want to
execute the following commands:

apt-cache showpkg libpng2
apt-cache showpkg libpng3

This problem has been fixed in version 1.0.12-3.woody.1 of libpng and
version 1.2.1-1.1.woody.1 of libpng3 for the current stable
distribution (woody) and in version 1.0.12-4 of libpng and version
1.2.1-2 of libpng3 for the unstable distribution (sid).

We recommend that you upgrade your libpng packages immediately and
restart programs and daemons that link to these libraries and read
external data, such as web browsers.

wget url
will fetch the file for you
dpkg -i f...