The "at" commands on Mac OS X 10.3.7 and earlier do not properly drop privileges, which allows local users to (1) delete arbitrary files via atrm, (2) execute arbitrary programs via the -f argument to batch, or (3) read arbitrary files via the -f argument to batch, which generates a job file that is readable by the local user.
https://exchange.xforce.ibmcloud.com/vulnerabilities/18981
http://www.kb.cert.org/vuls/id/678150
http://www.digitalmunition.com/DMA%5B2005-0127a%5D.txt
http://marc.info/?l=bugtraq&m=110685027017411&w=2
http://lists.apple.com/archives/security-announce/2005/Jan/msg00001.html