The strptime API in Libsystem in Apple Mac OS X before 10.5.6 allows context-dependent attackers to cause a denial of service (memory corruption and application crash) or execute arbitrary code via a crafted date string, related to improper memory allocation.
http://www.vupen.com/english/advisories/2008/3444
http://www.us-cert.gov/cas/techalerts/TA08-350A.html
http://www.securitytracker.com/id?1021406
http://www.securityfocus.com/bid/32881
http://www.securityfocus.com/bid/32839
http://support.apple.com/kb/HT3338
http://secunia.com/advisories/33179
http://lists.apple.com/archives/security-announce//2008//Dec/msg00000.html