What’s Vulnerable › Vulnerabilities

CVE-2021-32810: Data race in crossbeam-deque

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-08-02 · updated 2026-06-17
• Weakness: CWE-362

Description

crossbeam-deque is a package of work-stealing deques for building task schedulers when programming in Rust. In versions prior to 0.7.4 and 0.8.0, the result of the race condition is that one or more tasks in the worker queue can be popped twice instead of other tasks that are forgotten and never popped. If tasks are allocated on the heap, this can cause double free and a memory leak. If not, this still can cause a logical bug. Crates using `Stealer::steal`, `Stealer::steal_batch`, or `Stealer::steal_batch_and_pop` are affected by this issue. This has been fixed in crossbeam-deque 0.8.1 and 0.7.4.

Affected products

• crossbeam-rs crossbeam: before 0.7.4; from 0.8.0 before 0.8.1 — fixed in 0.7.4, 0.8.1
• Fedoraproject Fedora: 34

How to fix

Upgrade to a fixed version: crossbeam-rs crossbeam 0.7.4, 0.8.1. Check the vendor advisory for mitigations.

References

• https://github.com/crossbeam-rs/crossbeam/security/advisories/GHSA-pqqp-xmhj-wgcw
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7EZILHZDRGDPOBQ4KTW3E5PPMKLHGH5N/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWHNNBJCU4EHA2X5ZAMJMGLDUYS5FEPP/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AYBSLIYFANZLCYWOGTIYZUM26TJRH7WU/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CY5T3FCE4MUYSPKEWICLVJBBODGJ6SZE/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EW5B2VTDVMJ6B3DA4VLMAMW2GGDCE2BK/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCIBFGBSL3JSVJQTNEDEIMZGZF23N2KE/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OCLMH7B7B2MF55ET4NQNPH7JWISFX4RT/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RRPKBRXCRNGNMVFQPFD4LM3QKPEMBQQR/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TFUBWBYCPSSXTJGEAQ67CJUNQJBOCM26/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U3LSN3B43TJSFIOB3QLPBI3RCHRU5BLO/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VQZIEJQBV3S72BHD5GKJQF3NVYNRV5CF/

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