The epoll implementation in the Linux kernel 2.6.37.2 and earlier does not properly traverse a tree of epoll file descriptors, which allows local users to cause a denial of service (CPU consumption) via a crafted application that makes epoll_create and epoll_ctl system calls.
https://bugzilla.redhat.com/show_bug.cgi?id=681578
http://secunia.com/advisories/48964
http://secunia.com/advisories/48898
http://secunia.com/advisories/48410
http://secunia.com/advisories/48115
http://secunia.com/advisories/43522
http://rhn.redhat.com/errata/RHSA-2012-0862.html
http://openwall.com/lists/oss-security/2011/03/02/2
http://openwall.com/lists/oss-security/2011/03/02/1
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00013.html
http://lists.opensuse.org/opensuse-security-announce/2012-04/msg00021.html