Consul and Consul Enterprise's cluster peering implementation contained a flaw whereby a peer cluster with service of the same name as a local service could corrupt Consul state, resulting in denial of service. This vulnerability was resolved in Consul 1.14.5, and 1.15.3

Consul and Consul Enterprise allowed any user with service:write permissions to use Envoy extensions configured via service-defaults to patch remote proxy instances that target the configured service, regardless of whether the user has permission to modify the service(s) corresponding to those modified proxies.