Prevent http.DefaultServeMux exposure on CMSA#1197
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When the Prometheus /metrics endpoint is enabled, the HTTP server was initialized via `http.ListenAndServe(addr, nil)`, defaulting to the global `http.DefaultServeMux` Transitive third-party dependencies (like k8s libraries) register global debug and profiling handlers (/debug/pprof/*), these diagnostic and performance endpoints were unintentionally exposed publicly on the metrics port. So, we're isolating the /metrics endpoint by initializing a dedicated ServeMux. Tested on a live cluster with --metrics-address=0.0.0.0:8080 flag configured qqon the CMSA deployment: Metrics scraping still works: curl -i http://localhost:8080/metrics Profiling endpoints are no longer exposed as a side effect: curl -i http://localhost:8080/debug/pprof/
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When the Prometheus /metrics endpoint is enabled, the HTTP server was initialized via
http.ListenAndServe(addr, nil), defaulting to the globalhttp.DefaultServeMuxTransitive third-party dependencies (like k8s libraries) register global debug and profiling handlers (
/debug/pprof/*), these endpoints were unintentionally exposed publicly on the metrics port.So, we're isolating the
/metricsendpoint by initializing a dedicatedServeMux.Tested on a live cluster with
--metrics-address=0.0.0.0:8080flag configured on the CMSA deployment:Metrics scraping still works:
Profiling endpoints are no longer exposed as a side effect: