# CVE-2020-26962: Firefox ESR and 1 other: Cross-origin iframes that contained a login form could have been recognized by the login autofill service,…

CVE-2020-26962 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: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-26962
- Priority: Routine
- CVSS: 6.1 (Low)
- EPSS: 0.0070
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 16, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-26962

## Description

Cross-origin iframes that contained a login form could have been recognized by the login autofill service, and populated. This could have been used in clickjacking attacks, as well as be read across partitions in dynamic first party isolation. 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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Data as of 2026-11-08T13:06:02Z 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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