A NULL pointer dereference was found in pkg/proxy/envoy/v2/debug.go getResourceVersion in Istio pilot before 1.5.0-alpha.0. If a particular HTTP GET request is made to the pilot API endpoint, it is possible to cause the Go runtime to panic (resulting in a denial of service to the istio-pilot application).
https://github.com/istio/istio/compare/1.4.2...1.5.0-alpha.0