language-baselinelisted

## Baseline **Applies when:** Writing or committing code that builds SQL from non-literal values, runs a subprocess/shell with non-literal arguments, writes input into the DOM/HTML, resolves a filesystem path from input, deserializes untrusted data, executes a string as code, bypasses type-system checks, or issues an outbound HTTP request to an input-derived URL. **Always:** - Route SQL values through driver parameter binding; never string concatenation, f-strings, template literals, or ORM raw-query helpers. - Run subprocesses with an argv array and no shell (`shell=False`); the command name is a literal or from an allowlist, never derived from input. - Write user-controlled values to the DOM/HTML only through escaping sinks (`textContent`, not `innerHTML`/`document.write`); sanitize with a vetted library when raw HTML is required. - Normalize input-derived filesystem paths: strip to basename, join against a known-safe directory, resolve symlinks, and reject anything outside that directory. - Deserialize untrusted data only with type-constrained formats (`json.loads`, `yaml.safe_load`); never `pickle.loads`, unsafe `yaml.load`, `Marshal.load`, `ObjectInputStream`, or `unserialize`. - Never execute a string as code (`eval`, `new Function`, `setTimeout(stringArg)`) or bypass type-system checks (`as any`, `@ts-ignore`) on external input. - Before an outbound HTTP request to an input-derived URL, check the host against an allowlist and reject internal/link-local IP ranges. **