The remote host is missing an update to neon announced via advisory DSA 487-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20487-1

Multiple format string vulnerabilities were discovered in neon, an HTTP and WebDAV client library. These vulnerabilities could potentially be exploited by a malicious WebDAV server to execute arbitrary code with the privileges of the process using libneon. For the current stable distribution (woody) these problems have been fixed in version 0.19.3-2woody3. For the unstable distribution (sid), these problems have been fixed in version 0.24.5-1. We recommend that you update your neon package.