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 firefoxUpgrade thunderbird | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade firefox-debuginfoUpgrade firefoxUpgrade firefox-debugsource | Feb 20, 2026 | Jan 13, 2026 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Jan 19, 2026 | Jan 19, 2026 |
| Freebsd | — | Upgrade firefox-esrUpgrade thunderbirdUpgrade 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 Mozilla Firefox ESR version 140.7Upgrade to the latest version of Mozilla Firefox | 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 firefox-x11Upgrade thunderbirdUpgrade firefox | Jan 19, 2026 | Jan 13, 2026 |
| Redhat_linux | — | Upgrade thunderbirdUpgrade firefox-x11Upgrade thunderbird-debuginfoNo solution existsUpgrade firefox-debuginfoUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade firefox-debugsource | Jan 16, 2026 | Jan 13, 2026 |
| Rocky_linux | — | Upgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade firefoxUpgrade firefox-debuginfoUpgrade firefox-x11Upgrade firefox-debugsourceUpgrade thunderbird | Jan 19, 2026 | Jan 16, 2026 |
| Suse | — | Upgrade MozillaFirefox-translations-commonUpgrade MozillaThunderbirdUpgrade MozillaThunderbird-openpgp-librnpUpgrade MozillaFirefoxUpgrade MozillaThunderbird-translations-otherUpgrade mozillafirefox-branding-upstreamUpgrade MozillaFirefox-develUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-common | Jan 15, 2026 | Jan 15, 2026 |
| Ubuntu | — | Upgrade thunderbird | Feb 4, 2026 | Feb 2, 2026 |
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