The remote Debian host is missing a security-related update.
Several vulnerabilities were discovered in tinc, a Virtual Private Network (VPN) daemon. The Common Vulnerabilities and Exposures project identifies the following problems : - CVE-2018-16738 Michael Yonli discovered a flaw in the implementation of the authentication protocol that could allow a remote attacker to establish an authenticated, one-way connection with another node. - CVE-2018-16758 Michael Yonli discovered that a man-in-the-middle that has intercepted a TCP connection might be able to disable encryption of UDP packets sent by a node.
Upgrade the tinc packages. For the stable distribution (stretch), these problems have been fixed in version 1.0.31-1+deb9u1.