fish (aka fish-shell) 1.16.0 before 2.1.1 does not properly check the credentials, which allows local users to gain privileges via the universal variable socket, related to /tmp/fishd.socket.user permissions.
https://github.com/fish-shell/fish-shell/issues/1436
http://www.openwall.com/lists/oss-security/2014/04/28/4
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00071.html
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00059.html