See https://rustsec.org/advisories/RUSTSEC-2021-0145.html for the advisory. It has not been patched even though an already-reviewed [PR](https://github.com/softprops/atty/pull/51) is available for a long time. several projects e.g. [clap](https://github.com/clap-rs/clap/pull/4249) and [env_logger](https://github.com/rust-cli/env_logger/commit/066c2192c187f047ae178e786ff36e6cabed21f7) switched to `is_terminal`