Multiple buffer overflows in mDNSResponder before 625.41.2 allow remote attackers to read or write to out-of-bounds memory locations via vectors involving the (1) GetValueForIPv4Addr, (2) GetValueForMACAddr, (3) rfc3110_import, or (4) CopyNSEC3ResourceRecord function.
https://support.apple.com/HT206846
http://www.securitytracker.com/id/1036181
http://www.securityfocus.com/bid/91323
http://www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html