pnpm: Environment secrets exfiltrated via env-placeholder expansion in proxy settings read from an untrusted pnpm-workspace.yaml

Summary pnpm expands $VAR environment placeholders in the httpProxy / httpsProxy / noProxy settings read from a project's pnpm-workspace.yaml. Because a project manifest is repository-controlled, a malicious repository that a victim merely clones and runs pnpm install in can route all install...