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 thunderbirdUpgrade firefox | 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 firefox-debugsourceUpgrade firefox | May 4, 2026 | Apr 7, 2026 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Apr 10, 2026 | Apr 10, 2026 |
| Freebsd | — | Upgrade thunderbirdUpgrade thunderbird-esrUpgrade firefox-esrUpgrade firefox | Apr 17, 2026 | Apr 17, 2026 |
| Mfsa2026 25 | — | Upgrade to Mozilla Firefox version 149.0.2 | Apr 8, 2026 | Apr 7, 2026 |
| Mfsa2026 26 | — | Upgrade to Mozilla Firefox ESR version 115.34.1 | 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-debugsourceUpgrade thunderbird-debugsourceNo solution existsUpgrade thunderbirdUpgrade firefox-debuginfoUpgrade firefox-x11Upgrade firefoxUpgrade thunderbird-debuginfo | Apr 14, 2026 | Apr 7, 2026 |
| Rocky_linux | — | Upgrade firefox-x11Upgrade firefox-debuginfoUpgrade firefox-debugsourceUpgrade thunderbird-debuginfoUpgrade firefoxUpgrade thunderbirdUpgrade thunderbird-debugsource | Apr 16, 2026 | Apr 15, 2026 |
| Suse | — | Upgrade MozillaThunderbird-translations-commonUpgrade MozillaFirefox-translations-commonUpgrade MozillaThunderbirdUpgrade MozillaFirefox-develUpgrade MozillaFirefoxUpgrade MozillaFirefox-translations-otherUpgrade MozillaThunderbird-translations-other | Apr 14, 2026 | Apr 11, 2026 |
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