# CVE-2021-32810: firefox: crossbeam-deque is a package of work-stealing deques for building taskschedulers when programming in Rust

CVE-2021-32810 is fixed in 4 products on 1 platform, first by RHSA-2021:3755, released October 11, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-32810
- Priority: High
- CVSS: 9.8 (Medium)
- EPSS: 0.0191
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 2, 2021

## Description

crossbeam-deque is a package of work-stealing deques for building taskschedulers 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 workerqueue can be popped twice instead of other tasks that are forgotten andnever popped. If tasks are allocated on the heap, this can cause doublefree and a memory leak. If not, this still can cause a logical bug. Cratesusing `Stealer::steal`, `Stealer::steal_batch`, or`Stealer::steal_batch_and_pop` are affected by this issue. This has beenfixed in crossbeam-deque 0.8.1 and 0.7.4.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox RHEL 8 | 0:91.2.0-4.el8_4 | [RHSA-2021:3755](https://patchblox.com/security/data/fix/linux/rhsa-2021-3755.md) | Oct 11, 2021 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 93.0+build1-0ubuntu0.18.04.1 | [firefox 93.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-93.0-build1-0ubuntu0.18.04.1.md) | Nov 2, 2021 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 93.0+build1-0ubuntu0.20.04.1 | [firefox 93.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-93.0-build1-0ubuntu0.20.04.1.md) | Nov 2, 2021 |
| Linux | firefox Ubuntu 24.10 (oracular) | 93.0+build1-0ubuntu2 | [firefox 93.0+build1-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-firefox-93.0-build1-0ubuntu2.md) | Jan 16, 2026 |
| Linux | firefox Ubuntu 25.04 (plucky) | 93.0+build1-0ubuntu2 | [firefox 93.0+build1-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-firefox-93.0-build1-0ubuntu2.md) | Jan 16, 2026 |
| Linux | firefox ol 8 | 0:91.2.0-4.0.1.el8_4 | [ELSA-2021-3755](https://patchblox.com/security/data/fix/linux/elsa-2021-3755.md) | Oct 11, 2021 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 93.0+build1-0ubuntu0.18.04.1 | [firefox-geckodriver 93.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-93.0-build1-0ubuntu0.18.04.1.md) | Nov 2, 2021 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 93.0+build1-0ubuntu0.20.04.1 | [firefox-geckodriver 93.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-93.0-build1-0ubuntu0.20.04.1.md) | Nov 2, 2021 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 93.0+build1-0ubuntu0.18.04.1 | [firefox-mozsymbols 93.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-93.0-build1-0ubuntu0.18.04.1.md) | Nov 2, 2021 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 93.0+build1-0ubuntu0.20.04.1 | [firefox-mozsymbols 93.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-93.0-build1-0ubuntu0.20.04.1.md) | Nov 2, 2021 |
| Linux | thunderbird RHEL 8 | 0:91.2.0-1.el8_4 | [RHSA-2021:3838](https://patchblox.com/security/data/fix/linux/rhsa-2021-3838.md) | Oct 13, 2021 |
| Linux | thunderbird ol 8 | 0:91.2.0-1.0.1.el8_4 | [ELSA-2021-3838](https://patchblox.com/security/data/fix/linux/elsa-2021-3838.md) | Oct 15, 2021 |

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