# CVE-2021-38495: Mozilla Thunderbird and 1 other: Mozilla developers reported memory safety bugs present in Thunderbird 78.13.0.

CVE-2021-38495 is fixed in 7 products on 2 platforms, first by Mozilla Thunderbird (en-US) 91.1.2, released September 24, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-38495
- Priority: High
- CVSS: 8.8 (Medium)
- EPSS: 0.0111
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 2, 2021
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-38495

## Description

Mozilla developers reported memory safety bugs present in Thunderbird 78.13.0. 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 Thunderbird < 91.1 and Firefox ESR < 91.1.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Thunderbird (en-US) | 91.1.2 | [Mozilla Thunderbird (en-US) 91.1.2](https://patchblox.com/security/data/fix/windows-app/mozilla.thunderbird-91.1.2.md) | Sep 24, 2021 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | [thunderbird 1:91.5.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-91.5.0-build1-0ubuntu0.18.04.1.md) | Feb 16, 2023 |
| Linux | thunderbird Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | [thunderbird 1:91.5.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-1-91.5.0-build1-0ubuntu0.20.04.1.md) | Feb 16, 2023 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:91.5.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-91.5.0-build1-0ubuntu0.18.04.1.md) | Feb 16, 2023 |
| Linux | thunderbird-gnome-support Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | [thunderbird-gnome-support 1:91.5.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-gnome-support-1-91.5.0-build1-0ubuntu0.20.04.1.md) | Feb 16, 2023 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:91.5.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-91.5.0-build1-0ubuntu0.18.04.1.md) | Feb 16, 2023 |
| Linux | thunderbird-mozsymbols Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | [thunderbird-mozsymbols 1:91.5.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-mozsymbols-1-91.5.0-build1-0ubuntu0.20.04.1.md) | Feb 16, 2023 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:91.5.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-91.5.0-build1-0ubuntu0.18.04.1.md) | Feb 16, 2023 |
| Linux | xul-ext-calendar-timezones Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | [xul-ext-calendar-timezones 1:91.5.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-calendar-timezones-1-91.5.0-build1-0ubuntu0.20.04.1.md) | Feb 16, 2023 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:91.5.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-91.5.0-build1-0ubuntu0.18.04.1.md) | Feb 16, 2023 |
| Linux | xul-ext-gdata-provider Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | [xul-ext-gdata-provider 1:91.5.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-gdata-provider-1-91.5.0-build1-0ubuntu0.20.04.1.md) | Feb 16, 2023 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | [xul-ext-lightning 1:91.5.0+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-91.5.0-build1-0ubuntu0.18.04.1.md) | Feb 16, 2023 |
| Linux | xul-ext-lightning Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | [xul-ext-lightning 1:91.5.0+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-lightning-1-91.5.0-build1-0ubuntu0.20.04.1.md) | Feb 16, 2023 |

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