RUSTSEC-2018-0022: Use of uninitialized memory in temporary

What to do

1. See which version you have: cargo tree -i temporary (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p temporary. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example temporary = "0.6.4") or update the dependency that pulls it in.
3. Check again with cargo audit, or paste your Cargo.lock into our Cargo.toml checker.

Details from the advisory

Uninit memory is used as a RNG seed in temporary

The following function is used as a way to get entropy from the system, which does operations on and exposes uninit memory, which is UB.

fn random_seed(_: &Path, _: &str) -> [u64; 2] {
    use std::mem::uninitialized as rand;
    unsafe { [rand::<u64>() ^ 0x12345678, rand::<u64>() ^ 0x87654321] }
}

This has been resolved in the 0.6.4 release.

The crate is not intended to be used outside of a testing environment.

For a general purpose crate to create temporary directories, tempfile is an alternative for this crate.

References

• Package: crates.io/crates/temporary
• Advisory: rustsec.org/advisories/RUSTSEC-2018-0022.html
• Report: github.com/stainless-steel/temporary/issues/2

From the RustSec Advisory Database (CC0-1.0) via the OSV export, downloaded Oct 24, 2026. Severity score computed from the published CVSS vector.