CVE-2020-15254: Crossbeam Project Crossbeam

Critical severity, CVSS 9.8. EPSS: 2.7% chance of exploitation in the next 30 days.

Crossbeam is a set of tools for concurrent programming. In crossbeam-channel before version 0.4.4, the bounded channel incorrectly assumes that `Vec::from_iter` has allocated capacity that same as the number of iterator elements. `Vec::from_iter` does not actually guarantee that and may allocate extra memory. The destructor of the `bounded` channel reconstructs `Vec` from the raw pointer based on the incorrect assumes described above. This is unsound and causing deallocation with the incorrect capacity when `Vec::from_iter` has allocated different sizes with the number of iterator elements. This has been fixed in crossbeam-channel 0.4.4.

Affected products

Published 2020-10-16. Last modified 2026-06-17.