GHSA-6R69-C6WG-7G8M yopass Prometheus metrics middleware allows remote memory exhaustion through unbounded method labels

The Prometheus metrics middleware in pkg/server/server.go used r.Method directly as a label value on request counter and duration histogram metrics. Since the mux catch-all route matches any HTTP method, an unauthenticated attacker can send requests with arbitrary method strings e.g. curl -X "M1"...

yopass Prometheus metrics middleware allows remote memory exhaustion through unbounded method labels

The Prometheus metrics middleware in pkg/server/server.go used r.Method directly as a label value on request counter and duration histogram metrics. Since the mux catch-all route matches any HTTP method, an unauthenticated attacker can send requests with arbitrary method strings e.g. curl -X "M1"...