The (1) bos.rte.serv_aid or (2) bos.rte.console filesets in IBM AIX 5.1 and 5.2 allow local users to overwrite arbitrary files via a symlink attack on temporary files via unknown attack vectors.
https://techsupport.services.ibm.com/server/pseries.subscriptionSvcs?mode=18&ID=279
https://exchange.xforce.ibmcloud.com/vulnerabilities/16008
http://www.securityfocus.com/bid/10231
http://www-1.ibm.com/support/search.wss?rs=0&q=IY55790&apar=only
http://www-1.ibm.com/support/search.wss?rs=0&q=IY55789&apar=only