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.

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