The getSkillname function in the eve module in Conky 1.8.1 and earlier allows local users to overwrite arbitrary files via a symlink attack on /tmp/.cesf.
https://bugs.launchpad.net/ubuntu/+source/conky/+bug/607309
http://www.openwall.com/lists/oss-security/2011/10/10/8
http://www.openwall.com/lists/oss-security/2011/10/09/4
http://www.gentoo.org/security/en/glsa/glsa-201110-09.xml