CVE-2020-36469
An issue was discovered in the appendix crate through 2020-11-15 for Rust. For the generic K and V type parameters, Send and Sync are implemented unconditionally.
Date published : 2021-08-08
https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/appendix/RUSTSEC-2020-0149.md