# CVE-2020-15254: firefox: Crossbeam is a set of tools for concurrent programming

CVE-2020-15254 is fixed in 3 products on 1 platform, first by firefox 82.0+build2-0ubuntu0.18.04.1, released October 21, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-15254
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0270
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 21, 2020

## Description

Crossbeam is a set of tools for concurrent programming. Incrossbeam-channel before version 0.4.4, the bounded channel incorrectlyassumes that `Vec::from_iter` has allocated capacity that same as thenumber of iterator elements. `Vec::from_iter` does not actually guaranteethat and may allocate extra memory. The destructor of the `bounded` channelreconstructs `Vec` from the raw pointer based on the incorrect assumesdescribed above. This is unsound and causing deallocation with theincorrect capacity when `Vec::from_iter` has allocated different sizes withthe number of iterator elements. This has been fixed in crossbeam-channel0.4.4.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 82.0+build2-0ubuntu0.18.04.1 | [firefox 82.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-82.0-build2-0ubuntu0.18.04.1.md) | Oct 21, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 82.0+build2-0ubuntu0.20.04.1 | [firefox 82.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-82.0-build2-0ubuntu0.20.04.1.md) | Oct 21, 2020 |
| Linux | firefox Ubuntu 24.10 (oracular) | 82.0.2+build1-0ubuntu1 | [firefox 82.0.2+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-firefox-82.0.2-build1-0ubuntu1.md) | Oct 22, 2020 |
| Linux | firefox Ubuntu 25.04 (plucky) | 82.0.2+build1-0ubuntu1 | [firefox 82.0.2+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-firefox-82.0.2-build1-0ubuntu1.md) | Oct 22, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 82.0+build2-0ubuntu0.18.04.1 | [firefox-geckodriver 82.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-82.0-build2-0ubuntu0.18.04.1.md) | Oct 21, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 82.0+build2-0ubuntu0.20.04.1 | [firefox-geckodriver 82.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-82.0-build2-0ubuntu0.20.04.1.md) | Oct 21, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 82.0+build2-0ubuntu0.18.04.1 | [firefox-mozsymbols 82.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-82.0-build2-0ubuntu0.18.04.1.md) | Oct 21, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 82.0+build2-0ubuntu0.20.04.1 | [firefox-mozsymbols 82.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-82.0-build2-0ubuntu0.20.04.1.md) | Oct 21, 2020 |

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