# CVE-2020-26969: Firefox ESR and 1 other: Mozilla developers reported memory safety bugs present in Firefox 82.

CVE-2020-26969 is fixed in 4 products on 2 platforms, first by firefox 83.0+build2-0ubuntu0.18.04.2, released November 16, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-26969
- Priority: High
- CVSS: 8.8 (Medium)
- EPSS: 0.0122
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 16, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-26969

## Description

Mozilla developers reported memory safety bugs present in Firefox 82. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 83.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox ESR (en-US) | 91.0 | [Mozilla Firefox ESR (en-US) 91.0](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-91.0.md) | Aug 4, 2021 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 83.0+build2-0ubuntu0.18.04.2 | [firefox 83.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-83.0-build2-0ubuntu0.18.04.2.md) | Nov 16, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 83.0+build2-0ubuntu0.20.04.1 | [firefox 83.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-83.0-build2-0ubuntu0.20.04.1.md) | Nov 16, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 83.0+build2-0ubuntu0.18.04.2 | [firefox-geckodriver 83.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-83.0-build2-0ubuntu0.18.04.2.md) | Nov 16, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 83.0+build2-0ubuntu0.20.04.1 | [firefox-geckodriver 83.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-83.0-build2-0ubuntu0.20.04.1.md) | Nov 16, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 83.0+build2-0ubuntu0.18.04.2 | [firefox-mozsymbols 83.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-83.0-build2-0ubuntu0.18.04.2.md) | Nov 16, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 83.0+build2-0ubuntu0.20.04.1 | [firefox-mozsymbols 83.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-83.0-build2-0ubuntu0.20.04.1.md) | Nov 16, 2020 |

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