# CVE-2020-6805: Firefox ESR: When removing data about an origin whose tab was recently closed, a use-after-free could occur in the…

CVE-2020-6805 is fixed in 10 products on 2 platforms, first by firefox 74.0+build3-0ubuntu0.18.04.1, released March 10, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-6805
- Priority: High
- CVSS: 8.8 (Important)
- EPSS: 0.0149
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 10, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-6805

## Description

When removing data about an origin whose tab was recently closed, a use-after-free could occur in the Quota manager, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox ESR (en-US) | 78.0esr | [Mozilla Firefox ESR (en-US) 78.0esr](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-78.0esr.md) | Jun 25, 2020 |
| Linux | firefox RHEL 8 | 0:68.6.0-1.el8_1 | [RHSA-2020:0820](https://patchblox.com/security/data/fix/linux/rhsa-2020-0820.md) | Mar 16, 2020 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 74.0+build3-0ubuntu0.18.04.1 | [firefox 74.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-74.0-build3-0ubuntu0.18.04.1.md) | Mar 10, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 74.0+build3-0ubuntu1 | [firefox 74.0+build3-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-74.0-build3-0ubuntu1.md) | Mar 10, 2020 |
| Linux | firefox ol 8 | 0:68.6.0-1.0.1.el8_1 | [ELSA-2020-0820](https://patchblox.com/security/data/fix/linux/elsa-2020-0820.md) | Mar 16, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 74.0+build3-0ubuntu0.18.04.1 | [firefox-geckodriver 74.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-74.0-build3-0ubuntu0.18.04.1.md) | Mar 10, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 74.0+build3-0ubuntu1 | [firefox-geckodriver 74.0+build3-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-74.0-build3-0ubuntu1.md) | Mar 10, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 74.0+build3-0ubuntu0.18.04.1 | [firefox-mozsymbols 74.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-74.0-build3-0ubuntu0.18.04.1.md) | Mar 10, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 74.0+build3-0ubuntu1 | [firefox-mozsymbols 74.0+build3-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-74.0-build3-0ubuntu1.md) | Mar 10, 2020 |
| Linux | thunderbird RHEL 8 | 0:68.6.0-1.el8_1 | [RHSA-2020:0919](https://patchblox.com/security/data/fix/linux/rhsa-2020-0919.md) | Mar 23, 2020 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:68.7.0+build1-0ubuntu0.18.04.1 | [thunderbird 1:68.7.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-68.7.0-build1-0ubuntu0.18.04.1.md) | Apr 6, 2020 |
| Linux | thunderbird Ubuntu 20.04 LTS (focal) | 1:68.6.0+build2-0ubuntu1 | [thunderbird 1:68.6.0+build2-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-1-68.6.0-build2-0ubuntu1.md) | Mar 10, 2020 |
| Linux | thunderbird ol 8 | 0:68.6.0-1.0.1.el8_1 | [ELSA-2020-0919](https://patchblox.com/security/data/fix/linux/elsa-2020-0919.md) | Mar 23, 2020 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:68.7.0+build1-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:68.7.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-68.7.0-build1-0ubuntu0.18.04.1.md) | Apr 6, 2020 |
| Linux | thunderbird-gnome-support Ubuntu 20.04 LTS (focal) | 1:68.6.0+build2-0ubuntu1 | [thunderbird-gnome-support 1:68.6.0+build2-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-gnome-support-1-68.6.0-build2-0ubuntu1.md) | Mar 10, 2020 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:68.7.0+build1-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:68.7.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-68.7.0-build1-0ubuntu0.18.04.1.md) | Apr 6, 2020 |
| Linux | thunderbird-mozsymbols Ubuntu 20.04 LTS (focal) | 1:68.6.0+build2-0ubuntu1 | [thunderbird-mozsymbols 1:68.6.0+build2-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-mozsymbols-1-68.6.0-build2-0ubuntu1.md) | Mar 10, 2020 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:68.7.0+build1-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:68.7.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-68.7.0-build1-0ubuntu0.18.04.1.md) | Apr 6, 2020 |
| Linux | xul-ext-calendar-timezones Ubuntu 20.04 LTS (focal) | 1:68.6.0+build2-0ubuntu1 | [xul-ext-calendar-timezones 1:68.6.0+build2-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-calendar-timezones-1-68.6.0-build2-0ubuntu1.md) | Mar 10, 2020 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:68.7.0+build1-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:68.7.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-68.7.0-build1-0ubuntu0.18.04.1.md) | Apr 6, 2020 |
| Linux | xul-ext-gdata-provider Ubuntu 20.04 LTS (focal) | 1:68.6.0+build2-0ubuntu1 | [xul-ext-gdata-provider 1:68.6.0+build2-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-gdata-provider-1-68.6.0-build2-0ubuntu1.md) | Mar 10, 2020 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:68.7.0+build1-0ubuntu0.18.04.1 | [xul-ext-lightning 1:68.7.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-68.7.0-build1-0ubuntu0.18.04.1.md) | Apr 6, 2020 |
| Linux | xul-ext-lightning Ubuntu 20.04 LTS (focal) | 1:68.6.0+build2-0ubuntu1 | [xul-ext-lightning 1:68.6.0+build2-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-lightning-1-68.6.0-build2-0ubuntu1.md) | Mar 10, 2020 |

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