# CVE-2020-26979: Firefox ESR and 1 other: When a user typed a URL in the address bar or the search bar and quickly hit the enter key, a website…

CVE-2020-26979 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: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-26979
- Priority: Routine
- CVSS: 6.1 (Low)
- EPSS: 0.0073
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 14, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-26979

## Description

When a user typed a URL in the address bar or the search bar and quickly hit the enter key, a website could sometimes capture that event and then redirect the user before navigation occurred to the desired, entered address. To construct a convincing spoof the attacker would have had to guess what the user was typing, perhaps by suggesting it. 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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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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