SpotlightIndex in Apple OS X before 10.10.2 does not properly perform deserialization during access to a permission cache, which allows local users to read search results associated with other users' protected files via a Spotlight query.
https://exchange.xforce.ibmcloud.com/vulnerabilities/100529
http://www.securitytracker.com/id/1031650
http://support.apple.com/HT204244
http://lists.apple.com/archives/security-announce/2015/Jan/msg00003.html