The remote host is missing an update to clamav announced via advisory DSA 1281-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201281-1

Several remote vulnerabilities have been discovered in the Clam anti-virus toolkit. The Common Vulnerabilities and Exposures project identifies the following problems: CVE-2007-1745 It was discovered that a file descriptor leak in the CHM handler may lead to denial of service. CVE-2007-1997 It was discovered that a buffer overflow in the CAB handler may lead to the execution of arbitrary code. CVE-2007-2029 It was discovered that a file descriptor leak in the PDF handler may lead to denial of service. For the oldstable distribution (sarge) these problems have been fixed in version 0.84-2.sarge.16. For the stable distribution (etch) these problems have been fixed in version 0.90.1-3etch1. For the unstable distribution (sid) these problems have been fixed in version 0.90.2-1. We recommend that you upgrade your clamav packages. Packages for