FontParser in Apple iOS before 8.3 and Apple OS X before 10.10.3 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted font file.
https://support.apple.com/kb/HT204870
https://support.apple.com/HT204661
https://support.apple.com/HT204659
https://euvd.enisa.europa.eu/vulnerability/EUVD-2015-1236
http://lists.apple.com/archives/security-announce/2015/Apr/msg00002.html
http://lists.apple.com/archives/security-announce/2015/Apr/msg00001.html