An issue was discovered in the rcu_cell crate through 2020-11-14 for Rust. There are unconditional implementations of Send and Sync for RcuCell<T>.
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-36451.json"
[ { "events": [ { "introduced": "0" }, { "last_affected": "2020-11-14" } ] } ]