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 firefox-x11Upgrade firefoxUpgrade thunderbird | 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-debuginfoUpgrade firefox-debugsource | May 4, 2026 | Apr 7, 2026 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Apr 10, 2026 | Apr 10, 2026 |
| Freebsd | — | Upgrade firefox-esrUpgrade firefoxUpgrade thunderbird-esrUpgrade thunderbird | Apr 17, 2026 | Apr 17, 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 26 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 115.34.1 | 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 firefox-x11Upgrade thunderbirdUpgrade firefox | Apr 22, 2026 | Apr 7, 2026 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoUpgrade firefox-x11No solution existsUpgrade firefox-debuginfoUpgrade thunderbirdUpgrade firefoxUpgrade thunderbird-debugsourceUpgrade firefox-debugsource | Apr 14, 2026 | Apr 7, 2026 |
| Rocky_linux | — | Upgrade thunderbirdUpgrade thunderbird-debugsourceUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade firefox-debugsourceUpgrade firefoxUpgrade firefox-x11 | Apr 16, 2026 | Apr 15, 2026 |
| Suse | — | Upgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefoxUpgrade MozillaThunderbirdUpgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-devel | Apr 14, 2026 | Apr 11, 2026 |
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