The remote host is missing an update to libpng announced via advisory DSA 536-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20536-1

Chris Evans discovered several vulnerabilities in libpng: CVE-2004-0597 - Multiple buffer overflows exist, including when handling transparency chunk data, which could be exploited to cause arbitrary code to be executed when a specially crafted PNG image is processed CVE-2004-0598 - Multiple NULL pointer dereferences in png_handle_iCPP() and elsewhere could be exploited to cause an application to crash when a specially crafted PNG image is processed CVE-2004-0599 - Multiple integer overflows in png_handle_sPLT(), png_read_png() nctions and elsewhere could be exploited to cause an application to crash, or potentially arbitrary code to be executed, when a specially crafted PNG image is processed In addition, a bug related to CVE-2002-1363 was fixed: CVE-2004-0768 - A buffer overflow could be caused by incorrect calculation of buffer offsets, possibly leading to the execution of arbitrary code For the current stable distribution (woody), these problems have been fixed in libpng3 version 1.2.1-1.1.woody.7 and libpng version 1.0.12-3.woody.7. For the unstable distribution (sid), these problems will be fixed soon. We recommend that you update your libpng and libpng3 packages.