# CVE-2022-0566: Mozilla Thunderbird and 1 other: Out-of-bounds Write

CVE-2022-0566 is fixed in 7 products on 2 platforms, first by Mozilla Thunderbird (en-US) 91.6.1, released February 15, 2022. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2022-0566
- Priority: High
- CVSS: 9.8 (Important)
- EPSS: 0.0074
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 17, 2022
- Weakness: CWE-787: Out-of-bounds Write
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2022-0566

## Description

It may be possible for an attacker to craft an email message that causes Thunderbird to perform an out-of-bounds write of one byte when processing the message. This vulnerability affects Thunderbird < 91.6.1.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Thunderbird (en-US) | 91.6.1 | [Mozilla Thunderbird (en-US) 91.6.1](https://patchblox.com/security/data/fix/windows-app/mozilla.thunderbird-91.6.1.md) | Feb 15, 2022 |
| Linux | thunderbird Debian 11.6 (bullseye) | 1:91.6.1-1~deb11u1 | [DSA-5086-1](https://patchblox.com/security/data/fix/linux/dsa-5086-1.md) | Feb 23, 2022 |
| Linux | thunderbird Debian 12.15 (bookworm) | 1:91.6.1-1 | [DEBIAN-CVE-2022-0566](https://patchblox.com/security/data/fix/linux/debian-cve-2022-0566.md) | Dec 22, 2022 |
| Linux | thunderbird Debian 13.5 (trixie) | 1:91.6.1-1 | [DEBIAN-CVE-2022-0566](https://patchblox.com/security/data/fix/linux/debian-cve-2022-0566.md) | Dec 22, 2022 |
| Linux | thunderbird Debian 14 | 1:91.6.1-1 | [DEBIAN-CVE-2022-0566](https://patchblox.com/security/data/fix/linux/debian-cve-2022-0566.md) | Dec 22, 2022 |
| Linux | thunderbird RHEL 8 | 0:91.7.0-2.el8_5 | [RHSA-2022:0845](https://patchblox.com/security/data/fix/linux/rhsa-2022-0845.md) | Mar 14, 2022 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:91.7.0+build2-0ubuntu0.18.04.1 | [thunderbird 1:91.7.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-91.7.0-build2-0ubuntu0.18.04.1.md) | Mar 8, 2022 |
| Linux | thunderbird Ubuntu 20.04 LTS (focal) | 1:91.7.0+build2-0ubuntu0.20.04.1 | [thunderbird 1:91.7.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-1-91.7.0-build2-0ubuntu0.20.04.1.md) | Mar 8, 2022 |
| Linux | thunderbird Ubuntu 22.04.1 LTS (jammy) | 1:91.6.1+build1-0ubuntu1 | [thunderbird 1:91.6.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-thunderbird-1-91.6.1-build1-0ubuntu1.md) | Feb 17, 2022 |
| Linux | thunderbird almalinux 8 | 91.7.0-2.el8_5.alma | [ALSA-2022:0845](https://patchblox.com/security/data/fix/linux/alsa-2022-0845.md) | Mar 14, 2022 |
| Linux | thunderbird ol 8 | 0:91.7.0-2.0.1.el8_5 | [ELSA-2022-0845](https://patchblox.com/security/data/fix/linux/elsa-2022-0845.md) | Mar 14, 2022 |
| Linux | thunderbird rocky 8 | 0:91.7.0-2.el8_5 | [RLSA-2022:0845](https://patchblox.com/security/data/fix/linux/rlsa-2022-0845.md) | Mar 14, 2022 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:91.7.0+build2-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:91.7.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-91.7.0-build2-0ubuntu0.18.04.1.md) | Mar 8, 2022 |
| Linux | thunderbird-gnome-support Ubuntu 20.04 LTS (focal) | 1:91.7.0+build2-0ubuntu0.20.04.1 | [thunderbird-gnome-support 1:91.7.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-gnome-support-1-91.7.0-build2-0ubuntu0.20.04.1.md) | Mar 8, 2022 |
| Linux | thunderbird-gnome-support Ubuntu 22.04.1 LTS (jammy) | 1:91.6.1+build1-0ubuntu1 | [thunderbird-gnome-support 1:91.6.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-thunderbird-gnome-support-1-91.6.1-build1-0ubuntu1.md) | Feb 17, 2022 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:91.7.0+build2-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:91.7.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-91.7.0-build2-0ubuntu0.18.04.1.md) | Mar 8, 2022 |
| Linux | thunderbird-mozsymbols Ubuntu 20.04 LTS (focal) | 1:91.7.0+build2-0ubuntu0.20.04.1 | [thunderbird-mozsymbols 1:91.7.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-thunderbird-mozsymbols-1-91.7.0-build2-0ubuntu0.20.04.1.md) | Mar 8, 2022 |
| Linux | thunderbird-mozsymbols Ubuntu 22.04.1 LTS (jammy) | 1:91.6.1+build1-0ubuntu1 | [thunderbird-mozsymbols 1:91.6.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-thunderbird-mozsymbols-1-91.6.1-build1-0ubuntu1.md) | Feb 17, 2022 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:91.7.0+build2-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:91.7.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-91.7.0-build2-0ubuntu0.18.04.1.md) | Mar 8, 2022 |
| Linux | xul-ext-calendar-timezones Ubuntu 20.04 LTS (focal) | 1:91.7.0+build2-0ubuntu0.20.04.1 | [xul-ext-calendar-timezones 1:91.7.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-calendar-timezones-1-91.7.0-build2-0ubuntu0.20.04.1.md) | Mar 8, 2022 |
| Linux | xul-ext-calendar-timezones Ubuntu 22.04.1 LTS (jammy) | 1:91.6.1+build1-0ubuntu1 | [xul-ext-calendar-timezones 1:91.6.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-xul-ext-calendar-timezones-1-91.6.1-build1-0ubuntu1.md) | Feb 17, 2022 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:91.7.0+build2-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:91.7.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-91.7.0-build2-0ubuntu0.18.04.1.md) | Mar 8, 2022 |
| Linux | xul-ext-gdata-provider Ubuntu 20.04 LTS (focal) | 1:91.7.0+build2-0ubuntu0.20.04.1 | [xul-ext-gdata-provider 1:91.7.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-gdata-provider-1-91.7.0-build2-0ubuntu0.20.04.1.md) | Mar 8, 2022 |
| Linux | xul-ext-gdata-provider Ubuntu 22.04.1 LTS (jammy) | 1:91.6.1+build1-0ubuntu1 | [xul-ext-gdata-provider 1:91.6.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-xul-ext-gdata-provider-1-91.6.1-build1-0ubuntu1.md) | Feb 17, 2022 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:91.7.0+build2-0ubuntu0.18.04.1 | [xul-ext-lightning 1:91.7.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-91.7.0-build2-0ubuntu0.18.04.1.md) | Mar 8, 2022 |
| Linux | xul-ext-lightning Ubuntu 20.04 LTS (focal) | 1:91.7.0+build2-0ubuntu0.20.04.1 | [xul-ext-lightning 1:91.7.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-xul-ext-lightning-1-91.7.0-build2-0ubuntu0.20.04.1.md) | Mar 8, 2022 |
| Linux | xul-ext-lightning Ubuntu 22.04.1 LTS (jammy) | 1:91.6.1+build1-0ubuntu1 | [xul-ext-lightning 1:91.6.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-xul-ext-lightning-1-91.6.1-build1-0ubuntu1.md) | Feb 17, 2022 |

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