# CVE-2020-15670: Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox for Android 79.

CVE-2020-15670 is fixed in 11 products on 2 platforms, first by firefox 80.0+build2-0ubuntu0.18.04.1, released August 25, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-15670
- Priority: High
- CVSS: 8.8 (Medium)
- EPSS: 0.0107
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 25, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-15670

## Description

Mozilla developers reported memory safety bugs present in Firefox for Android 79. 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 < 80, Firefox ESR < 78.2, Thunderbird < 78.2, and Firefox for Android < 80.

## 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 |
| Windows apps | Mozilla Thunderbird (en-US) | 78.2.1 | [Mozilla Thunderbird (en-US) 78.2.1](https://patchblox.com/security/data/fix/windows-app/mozilla.thunderbird-78.2.1.md) | Aug 28, 2020 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 80.0+build2-0ubuntu0.18.04.1 | [firefox 80.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-80.0-build2-0ubuntu0.18.04.1.md) | Aug 25, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 80.0+build2-0ubuntu0.20.04.1 | [firefox 80.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-80.0-build2-0ubuntu0.20.04.1.md) | Aug 25, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 80.0+build2-0ubuntu0.18.04.1 | [firefox-geckodriver 80.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-80.0-build2-0ubuntu0.18.04.1.md) | Aug 25, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 80.0+build2-0ubuntu0.20.04.1 | [firefox-geckodriver 80.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-80.0-build2-0ubuntu0.20.04.1.md) | Aug 25, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 80.0+build2-0ubuntu0.18.04.1 | [firefox-mozsymbols 80.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-80.0-build2-0ubuntu0.18.04.1.md) | Aug 25, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 80.0+build2-0ubuntu0.20.04.1 | [firefox-mozsymbols 80.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-80.0-build2-0ubuntu0.20.04.1.md) | Aug 25, 2020 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | [thunderbird 1:78.8.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-78.8.1-build1-0ubuntu0.18.04.1.md) | Apr 22, 2021 |
| Linux | thunderbird Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | [thunderbird 1:78.7.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-1-78.7.1-build1-0ubuntu0.20.04.1.md) | Jan 25, 2021 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:78.8.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-78.8.1-build1-0ubuntu0.18.04.1.md) | Apr 22, 2021 |
| Linux | thunderbird-gnome-support Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | [thunderbird-gnome-support 1:78.7.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-gnome-support-1-78.7.1-build1-0ubuntu0.20.04.1.md) | Jan 25, 2021 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:78.8.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-78.8.1-build1-0ubuntu0.18.04.1.md) | Apr 22, 2021 |
| Linux | thunderbird-mozsymbols Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | [thunderbird-mozsymbols 1:78.7.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-mozsymbols-1-78.7.1-build1-0ubuntu0.20.04.1.md) | Jan 25, 2021 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:78.8.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-78.8.1-build1-0ubuntu0.18.04.1.md) | Apr 22, 2021 |
| Linux | xul-ext-calendar-timezones Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | [xul-ext-calendar-timezones 1:78.7.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-calendar-timezones-1-78.7.1-build1-0ubuntu0.20.04.1.md) | Jan 25, 2021 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:78.8.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-78.8.1-build1-0ubuntu0.18.04.1.md) | Apr 22, 2021 |
| Linux | xul-ext-gdata-provider Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | [xul-ext-gdata-provider 1:78.7.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-gdata-provider-1-78.7.1-build1-0ubuntu0.20.04.1.md) | Jan 25, 2021 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | [xul-ext-lightning 1:78.8.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-78.8.1-build1-0ubuntu0.18.04.1.md) | Apr 22, 2021 |
| Linux | xul-ext-lightning Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | [xul-ext-lightning 1:78.7.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-lightning-1-78.7.1-build1-0ubuntu0.20.04.1.md) | Jan 25, 2021 |

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