Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
ISC DHCP is not affected. It doesn't perform DNSSEC validation. This is a BIND server-side issue. ISC DHCP uses portions of the ISC BIND libraries (primarily libdns, omapi, and libisccfg) only to support DDNS (TSIG support, DNS message construction/parsing, DHCID generation), OMAPI related operations, basic functions (configuration handling, data structures, logging, networking primitives), not for DNSSEC.