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.

The Gentoo net-im/jabberd2 package through 2.6.1 installs jabberd, jabberd2-c2s, jabberd2-router, jabberd2-s2s, and jabberd2-sm in /usr/bin owned by the jabber account, which might allow local users to gain privileges by leveraging access to this account and then waiting for root to execute one of these programs.