rss-newsfeed.php in Nagios Core 3.4.4, 3.5.1, and earlier, when MAGPIE_CACHE_ON is set to 1, allows local users to overwrite arbitrary files via a symlink attack on /tmp/magpie_cache.
https://www.nagios.org/projects/nagios-core/history/4x/
https://bugzilla.redhat.com/show_bug.cgi?id=958002