Heap-based buffer overflow in the php_quot_print_encode function in ext/standard/quot_print.c in PHP before 5.3.26 and 5.4.x before 5.4.16 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted argument to the quoted_printable_encode function.
https://bugs.php.net/bug.php?id=64879
http://www.ubuntu.com/usn/USN-1872-1
http://www.securityfocus.com/bid/60411
http://www.php.net/ChangeLog-5.php
http://support.apple.com/kb/HT5880
http://lists.apple.com/archives/security-announce/2013/Sep/msg00002.html