---
id: CVE-2021-32810
aliases:
  - GHSA-pqqp-xmhj-wgcw
  - RUSTSEC-2021-0093
title: crossbeam-deque Data Race before v0.7.4 and v0.8.1
summary: crossbeam-deque Data Race before v0.7.4 and v0.8.1
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
vendor: crossbeam-deque
product: crossbeam-deque
ecosystem: rust
affected:
  - crossbeam-deque < 0.7.4
  - 'crossbeam-deque >= 0.8.0, < 0.8.1'
patched:
  - crossbeam-deque 0.7.4
  - crossbeam-deque 0.8.1
published: '2021-08-25'
updated: '2026-07-08'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-pqqp-xmhj-wgcw'
references:
  - url: >-
      https://github.com/crossbeam-rs/crossbeam/security/advisories/GHSA-pqqp-xmhj-wgcw
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2021-32810'
  - url: 'https://rustsec.org/advisories/RUSTSEC-2021-0093.html'
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZQDIBB7VR3ER52FMSMNJPAWNDO5SITCE
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XFBZWCLG7AGLJO4A7K5IMJVPLSWZ5TJP
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WGB2H35CTZDHOV3VLC5BM6VFGURLLVRP
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VQZIEJQBV3S72BHD5GKJQF3NVYNRV5CF
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U3LSN3B43TJSFIOB3QLPBI3RCHRU5BLO
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TFUBWBYCPSSXTJGEAQ67CJUNQJBOCM26
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RRPKBRXCRNGNMVFQPFD4LM3QKPEMBQQR
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OCLMH7B7B2MF55ET4NQNPH7JWISFX4RT
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LCIBFGBSL3JSVJQTNEDEIMZGZF23N2KE
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/EW5B2VTDVMJ6B3DA4VLMAMW2GGDCE2BK
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CY5T3FCE4MUYSPKEWICLVJBBODGJ6SZE
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AYBSLIYFANZLCYWOGTIYZUM26TJRH7WU
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AWHNNBJCU4EHA2X5ZAMJMGLDUYS5FEPP
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7EZILHZDRGDPOBQ4KTW3E5PPMKLHGH5N
  - url: 'https://github.com/crossbeam-rs/crossbeam'
tags:
  - osv
  - rust
epss: 0.01923
epssPercentile: 0.79069
ingestedAt: '2026-07-09T18:56:37.322Z'
---

## Overview

### Impact

In the affected version of this crate, 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.

### Patches

This has been fixed in crossbeam-deque 0.8.1 and 0.7.4.

### Credits

This issue was reported and fixed by Maor Kleinberger.

### License

This advisory is in the public domain.

## Affected packages

- `crossbeam-deque < 0.7.4`
- `crossbeam-deque >= 0.8.0, < 0.8.1`

## Remediation

Upgrade to a patched release:

- `crossbeam-deque 0.7.4`
- `crossbeam-deque 0.8.1`