A malicious client which is allowed to send very large amounts of traffic (billions of packets) to a DHCP server can eventually overflow a 32-bit reference counter, potentially causing dhcpd to crash. Affects ISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0.
www.securityfocus.com/bid/103188
www.securitytracker.com/id/1040437
access.redhat.com/errata/RHSA-2018:0469
access.redhat.com/errata/RHSA-2018:0483
kb.isc.org/docs/aa-01567
lists.debian.org/debian-lts-announce/2018/03/msg00015.html
usn.ubuntu.com/3586-1/
usn.ubuntu.com/3586-2/
www.debian.org/security/2018/dsa-4133