The remote Debian host is missing a security-related update.
Multiple integer overflows have been discovered in Expat, an XML parsing C library, which may result in denial of service or the execution of arbitrary code if a malformed XML file is processed.
Upgrade the expat packages. For the oldstable distribution (wheezy), this problem has been fixed in version 2.1.0-1+deb7u2. For the stable distribution (jessie), this problem has been fixed in version 2.1.0-6+deb8u1.