dhcp is vulnerable to denial of service. Double-deletion of the released addresses in the dhcpv6 code allows an attacker to crash the process.
access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/7.7_release_notes/index
access.redhat.com/errata/RHSA-2019:2060
access.redhat.com/errata/RHSA-2019:3525
access.redhat.com/security/updates/classification/#moderate
bugs.debian.org/cgi-bin/bugreport.cgi?bug=896122
bugzilla.redhat.com/show_bug.cgi?id=1574292
bugzilla.redhat.com/show_bug.cgi?id=1613174
bugzilla.redhat.com/show_bug.cgi?id=1623792
bugzilla.redhat.com/show_bug.cgi?id=1672308
bugzilla.redhat.com/show_bug.cgi?id=1677382
lists.opensuse.org/opensuse-security-announce/2019-10/msg00048.html
lists.opensuse.org/opensuse-security-announce/2019-10/msg00049.html