CVE-2022-23639: Improper Restriction of Operations within the Bounds of a Memory Buffer and Race Condition in crossbeam-utils

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2022-02-15 · updated 2026-06-17
Weakness: CWE-362

Description

crossbeam-utils provides atomics, synchronization primitives, scoped threads, and other utilities for concurrent programming in Rust. crossbeam-utils prior to version 0.8.7 incorrectly assumed that the alignment of `{i,u}64` was always the same as `Atomic{I,U}64`. However, the alignment of `{i,u}64` on a 32-bit target can be smaller than `Atomic{I,U}64`. This can cause unaligned memory accesses and data race. Crates using `fetch_*` methods with `AtomicCell<{i,u}64>` are affected by this issue. 32-bit targets without `Atomic{I,U}64` and 64-bit targets are not affected by this issue. This has been fixed in crossbeam-utils 0.8.7. There are currently no known workarounds.

Affected products

crossbeam-rs crossbeam: before 0.8.7 — fixed in 0.8.7

How to fix

Upgrade to a fixed version: crossbeam-rs crossbeam 0.8.7. Check the vendor advisory for mitigations.

References

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