# CVE-2020-35114: Firefox ESR and 1 other: Mozilla developers reported memory safety bugs present in Firefox 83.

CVE-2020-35114 is fixed in 4 products on 2 platforms, first by firefox 84.0+build3-0ubuntu0.18.04.1, released December 14, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-35114
- Priority: High
- CVSS: 8.8 (Medium)
- EPSS: 0.0105
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 14, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-35114

## Description

Mozilla developers reported memory safety bugs present in Firefox 83. 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 < 84.

## 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) | 84.0+build3-0ubuntu0.18.04.1 | [firefox 84.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-84.0-build3-0ubuntu0.18.04.1.md) | Dec 14, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 84.0+build3-0ubuntu0.20.04.1 | [firefox 84.0+build3-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-84.0-build3-0ubuntu0.20.04.1.md) | Dec 14, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 84.0+build3-0ubuntu0.18.04.1 | [firefox-geckodriver 84.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-84.0-build3-0ubuntu0.18.04.1.md) | Dec 14, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 84.0+build3-0ubuntu0.20.04.1 | [firefox-geckodriver 84.0+build3-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-84.0-build3-0ubuntu0.20.04.1.md) | Dec 14, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 84.0+build3-0ubuntu0.18.04.1 | [firefox-mozsymbols 84.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-84.0-build3-0ubuntu0.18.04.1.md) | Dec 14, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 84.0+build3-0ubuntu0.20.04.1 | [firefox-mozsymbols 84.0+build3-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-84.0-build3-0ubuntu0.20.04.1.md) | Dec 14, 2020 |

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