Memory safety bugs present in Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. 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 149.0.2, Firefox ESR 140.9.1, Thunderbird 149.0.2, and Thunderbird 140.9.1.
CVSS Details
- CVSS 3.1 Base Score: 9.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/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 firefox-x11Upgrade firefoxUpgrade thunderbird | Apr 16, 2026 | Apr 13, 2026 |
| Amazon Linux Ami 2 | — | Upgrade firefoxUpgrade thunderbird | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade firefox-debuginfoUpgrade firefoxUpgrade firefox-debugsource | May 4, 2026 | Apr 7, 2026 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Apr 10, 2026 | Apr 10, 2026 |
| Freebsd | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-esr | Apr 10, 2026 | Apr 9, 2026 |
| Mfsa2026 25 | — | Upgrade to Mozilla Firefox version 149.0.2 | Apr 8, 2026 | Apr 7, 2026 |
| Mfsa2026 27 | — | Upgrade to Mozilla Firefox ESR version 140.9.1 | Apr 8, 2026 | Apr 7, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 140.9.1 | Apr 8, 2026 | Apr 7, 2026 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-x11 | Apr 22, 2026 | Apr 7, 2026 |
| Redhat_linux | — | Upgrade firefox-debuginfoUpgrade thunderbird-debugsourceUpgrade firefox-x11Upgrade thunderbirdNo solution existsUpgrade thunderbird-debuginfoUpgrade firefoxUpgrade firefox-debugsource | Apr 14, 2026 | Apr 7, 2026 |
| Rocky_linux | — | Upgrade firefox-debugsourceUpgrade firefox-x11Upgrade thunderbirdUpgrade firefox-debuginfoUpgrade firefoxUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfo | Apr 16, 2026 | Apr 15, 2026 |
| Suse | — | Upgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefoxUpgrade MozillaFirefox-develUpgrade MozillaThunderbird-translations-otherUpgrade MozillaThunderbird | Apr 14, 2026 | Apr 11, 2026 |
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