The PEAR_REST class in REST.php in PEAR in PHP through 5.6.0 allows local users to write to arbitrary files via a symlink attack on a (1) rest.cachefile or (2) rest.cacheid file in /tmp/pear/cache/, related to the retrieveCacheFirst and useLocalCache functions.
http://www.oracle.com/technetwork/topics/security/bulletinjan2015-2370101.html
http://www.openwall.com/lists/oss-security/2014/08/27/3
http://lists.opensuse.org/opensuse-updates/2014-09/msg00055.html
http://lists.opensuse.org/opensuse-updates/2014-09/msg00024.html