The remote host is missing an update to libpng announced via advisory DSA 2032-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202032-1

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-2009-2042 libpng does not properly parse 1-bit interlaced images with width values that are not divisible by 8, which causes libpng to include uninitialized bits in certain rows of a PNG file and might allow remote attackers to read portions of sensitive memory via out-of-bounds pixels in the file. CVE-2010-0205 libpng 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 For the stable distribution (lenny), these problems have been fixed in version 1.2.27-2+lenny3. For the testing (squeeze) and unstable (sid) distribution, these problems have been fixed in version 1.2.43-1 We recommend that you upgrade your libpng package.