Advisories for Golang/Go.opentelemetry.io/Contrib/Instrumentation/Net/Http/Otelhttp package

OpenTelemetry-Go Contrib is a collection of third-party packages for OpenTelemetry-Go. A handler wrapper out of the box adds labels http.user_agent and http.method that have unbound cardinality. It leads to the server's potential memory exhaustion when many malicious requests are sent to it. HTTP header User-Agent or HTTP method for requests can be easily set by an attacker to be random and long. The library internally uses httpconv.ServerRequest that records every …

opentelemetry-go-contrib is a collection of extensions for OpenTelemetry-Go. The v0.38.0 release of go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp uses the httpconv.ServerRequest function to annotate metric measurements for the http.server.request_content_length, http.server.response_content_length, and http.server.duration instruments. The ServerRequest function sets the http.target attribute value to be the whole request URI (including the query string)[^1]. The metric instruments do not "forget" previous measurement attributes when cumulative temporality is used, this means the cardinality of the measurements allocated is directly …