RUSTSEC-2020-0106: Queues allow non-Send types to be sent to other threads, allowing data races

What to do

1. See which version you have: cargo tree -i multiqueue2 (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p multiqueue2. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example multiqueue2 = "0.1.7") 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

Affected versions of this crate unconditionally implemented Send for types used in queue implementations (InnerSend<RW, T>, InnerRecv<RW, T>, FutInnerSend<RW, T>, FutInnerRecv<RW, T>).

This allows users to send non-Send types to other threads, which can lead to data race bugs or other undefined behavior.

The flaw was corrected in v0.1.7 by adding T: Send bound to to the Send impl of four data types explained above.

References

• Package: crates.io/crates/multiqueue2
• Advisory: rustsec.org/advisories/RUSTSEC-2020-0106.html
• Report: github.com/abbychau/multiqueue2/issues/10

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