CVE-2017-18226
The Gentoo net-im/jabberd2 package through 2.6.1 sets the ownership of /var/run/jabber to the jabber account, which might allow local users to kill arbitrary processes by leveraging access to this account for PID file modification before a root script executes a "kill -TERM `cat /var/run/jabber/filename.pid`" command.
Source: CVE-2017-18226