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 firefoxUpgrade thunderbirdUpgrade firefox-x11 | Apr 16, 2026 | Apr 13, 2026 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade firefox | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade firefoxUpgrade firefox-debugsourceUpgrade firefox-debuginfo | May 4, 2026 | Apr 7, 2026 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Apr 10, 2026 | Apr 10, 2026 |
| Freebsd | — | Upgrade firefox-esrUpgrade thunderbirdUpgrade firefox | Apr 10, 2026 | Apr 9, 2026 |
| Mfsa2026 25 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 149.0.2 | Apr 8, 2026 | Apr 7, 2026 |
| Mfsa2026 27 | — | Upgrade to Mozilla Firefox ESR version 140.9.1Upgrade to the latest version of Mozilla Firefox | Apr 8, 2026 | Apr 7, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 140.9.1Upgrade to the latest version of Mozilla Thunderbird | Apr 8, 2026 | Apr 7, 2026 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-x11 | Apr 22, 2026 | Apr 7, 2026 |
| Redhat_linux | — | No solution existsUpgrade firefox-debugsourceUpgrade thunderbirdUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade firefox-debuginfoUpgrade firefox-x11Upgrade thunderbird-debuginfo | Apr 14, 2026 | Apr 7, 2026 |
| Rocky_linux | — | Upgrade firefox-x11Upgrade firefox-debugsourceUpgrade firefoxUpgrade firefox-debuginfoUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade thunderbird | Apr 16, 2026 | Apr 15, 2026 |
| Suse | — | Upgrade MozillaFirefox-develUpgrade MozillaThunderbirdUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefox-translations-otherUpgrade MozillaFirefoxUpgrade MozillaFirefox-translations-commonUpgrade MozillaThunderbird-translations-common | Apr 14, 2026 | Apr 11, 2026 |
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