The remote Debian host is missing a security-related update.
Two vulnerabilities have been found in the PostgreSQL database system : - CVE-2018-10915 Andrew Krasichkov discovered that libpq did not reset all its connection state during reconnects. - CVE-2018-10925 It was discovered that some 'CREATE TABLE' statements could disclose server memory. For additional information please refer to the upstream announcement at https://www.postgresql.org/about/news/1878/
Upgrade the postgresql-9.6 packages. For the stable distribution (stretch), these problems have been fixed in version 9.6.10-0+deb9u1.