HashiCorp Consul and Consul Enterprise could crash when configured with an abnormally-formed service-router entry. Introduced in 1.6.0, fixed in 1.6.6 and 1.7.4.
https://github.com/hashicorp/consul/pull/7783
https://github.com/hashicorp/consul/blob/v1.7.4/CHANGELOG.md
https://github.com/hashicorp/consul/blob/v1.6.6/CHANGELOG.md