The scan function in ext/date/lib/parse_iso_intervals.c in PHP through 5.5.6 does not properly restrict creation of DateInterval objects, which might allow remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted interval specification.
https://support.apple.com/HT204659
https://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c04463322
https://bugs.php.net/bug.php?id=66060
http://www.ubuntu.com/usn/USN-2055-1
http://www.debian.org/security/2013/dsa-2816
http://rhn.redhat.com/errata/RHSA-2014-1765.html
http://lists.opensuse.org/opensuse-updates/2013-12/msg00126.html
http://lists.opensuse.org/opensuse-updates/2013-12/msg00125.html
http://lists.apple.com/archives/security-announce/2015/Apr/msg00001.html
http://git.php.net/?p=php-src.git%3Ba=commit%3Bh=12fe4e90be7bfa2a763197079f68f5568a14e071