Memory safety bugs present in Firefox ESR 115.34.0, 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 115.34.1, 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 thunderbirdUpgrade firefoxUpgrade firefox-x11 | Apr 16, 2026 | Apr 13, 2026 |
| Amazon Linux Ami 2 | — | Upgrade firefoxUpgrade thunderbird | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade firefoxUpgrade firefox-debuginfoUpgrade firefox-debugsource | May 4, 2026 | Apr 7, 2026 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Apr 10, 2026 | Apr 10, 2026 |
| Freebsd | — | Upgrade thunderbird-esrUpgrade thunderbirdUpgrade firefoxUpgrade firefox-esr | Apr 17, 2026 | Apr 17, 2026 |
| Mfsa2026 25 | — | Upgrade to Mozilla Firefox version 149.0.2Upgrade to the latest version of Mozilla Firefox | Apr 8, 2026 | Apr 7, 2026 |
| Mfsa2026 26 | — | Upgrade to Mozilla Firefox ESR version 115.34.1Upgrade to the latest version of Mozilla Firefox | Apr 8, 2026 | Apr 7, 2026 |
| Mfsa2026 27 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 140.9.1 | Apr 8, 2026 | Apr 7, 2026 |
| Mozilla Thunderbird | — | Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 140.9.1 | Apr 8, 2026 | Apr 7, 2026 |
| Oracle_linux | — | Upgrade firefoxUpgrade thunderbirdUpgrade firefox-x11 | Apr 22, 2026 | Apr 7, 2026 |
| Redhat_linux | — | Upgrade firefox-x11Upgrade thunderbird-debugsourceUpgrade firefoxUpgrade firefox-debuginfoUpgrade thunderbirdNo solution existsUpgrade thunderbird-debuginfoUpgrade firefox-debugsource | Apr 14, 2026 | Apr 7, 2026 |
| Rocky_linux | — | Upgrade thunderbird-debugsourceUpgrade thunderbirdUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade firefox-debugsourceUpgrade firefoxUpgrade firefox-x11 | Apr 16, 2026 | Apr 15, 2026 |
| Suse | — | Upgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefoxUpgrade MozillaThunderbirdUpgrade MozillaFirefox-develUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-other | Apr 14, 2026 | Apr 11, 2026 |
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