ext/spl/spl_array.c in PHP before 5.6.26 and 7.x before 7.0.11 proceeds with SplArray unserialization without validating a return value and data type, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via crafted serialized data.
www.openwall.com/lists/oss-security/2016/09/15/10
www.php.net/ChangeLog-5.php
www.php.net/ChangeLog-7.php
www.securityfocus.com/bid/93007
www.securitytracker.com/id/1036836
access.redhat.com/errata/RHSA-2018:1296
bugs.php.net/bug.php?id=73029
github.com/php/php-src/commit/ecb7f58a069be0dec4a6131b6351a761f808f22e?w=1
security.gentoo.org/glsa/201611-22
www.tenable.com/security/tns-2016-19