libpng - several vulnerabilities

Several vulnerabilities have been discovered in libpng, a library for
reading and writing PNG files. The Common Vulnerabilities and
Exposures project identifies the following problems:

• CVE-2010-1205
  It was discovered a buffer overflow in libpng which allows remote
  attackers to execute arbitrary code via a PNG image that triggers
  an additional data row.
• CVE-2010-2249
  It was discovered a memory leak in libpng which allows remote
  attackers to cause a denial of service (memory consumption and
  application crash) via a PNG image containing malformed Physical
  Scale (aka sCAL) chunks.

For the stable distribution (lenny), these problems have been fixed in
version 1.2.27-2+lenny4.

For the testing (squeeze) and unstable (sid) distribution, these
problems have been fixed in version 1.2.44-1.

We recommend that you upgrade your libpng package.