The remote Debian host is missing a security-related update.
Aleksandar Nikolic of Cisco Talos discovered a stack-based buffer overflow vulnerability in libsoup2.4, a HTTP library implementation in C. A remote attacker can take advantage of this flaw by sending a specially crafted HTTP request to cause an application using the libsoup2.4 library to crash (denial of service), or potentially execute arbitrary code.
Upgrade the libsoup2.4 packages. For the oldstable distribution (jessie), this problem has been fixed in version 2.48.0-1+deb8u1. For the stable distribution (stretch), this problem has been fixed in version 2.56.0-2+deb9u1.