Memory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146. 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 was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
CVSS Details
- CVSS 3.1 Base Score: 8.1
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade firefoxUpgrade firefox-x11Upgrade thunderbird | Jan 20, 2026 | Jan 15, 2026 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade firefox | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade firefox-debugsourceUpgrade firefox-debuginfoUpgrade firefox | Feb 20, 2026 | Jan 13, 2026 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Jan 19, 2026 | Jan 19, 2026 |
| Freebsd | — | Upgrade thunderbirdUpgrade firefox-esrUpgrade firefox | Jan 27, 2026 | Jan 15, 2026 |
| Mfsa2026 01 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 147.0 | Jan 14, 2026 | Jan 13, 2026 |
| Mfsa2026 03 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 140.7 | Jan 14, 2026 | Jan 13, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 140.7Upgrade to the latest version of Mozilla Thunderbird | Jan 16, 2026 | Jan 13, 2026 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-x11 | Jan 19, 2026 | Jan 13, 2026 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoUpgrade firefox-debugsourceUpgrade firefoxUpgrade thunderbird-debugsourceNo solution existsUpgrade firefox-debuginfoUpgrade firefox-x11Upgrade thunderbird | Jan 16, 2026 | Jan 13, 2026 |
| Rocky_linux | — | Upgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade thunderbird-debuginfoUpgrade firefox-x11Upgrade firefox-debuginfoUpgrade thunderbird | Jan 19, 2026 | Jan 16, 2026 |
| Suse | — | Upgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefox-develUpgrade MozillaThunderbird-translations-commonUpgrade mozillafirefox-branding-upstreamUpgrade MozillaFirefoxUpgrade MozillaThunderbird-openpgp-librnpUpgrade MozillaFirefox-translations-commonUpgrade MozillaThunderbird | Jan 15, 2026 | Jan 15, 2026 |
| Ubuntu | — | Upgrade thunderbird | Feb 4, 2026 | Feb 2, 2026 |
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