Icecast before 2.4.0 does not change the supplementary group privileges when <changeowner> is configured, which allows local users to gain privileges via unspecified vectors.
https://bugzilla.redhat.com/show_bug.cgi?id=1168146
http://seclists.org/oss-sec/2014/q4/802
http://seclists.org/oss-sec/2014/q4/794
http://lists.opensuse.org/opensuse-updates/2014-12/msg00037.html