Memory safety bugs present in Firefox ESR 140.9, Thunderbird ESR 140.9, Firefox 149 and Thunderbird 149. 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 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
CVSS Details
- CVSS 3.1 Base Score: 7.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade firefoxUpgrade firefox-x11Upgrade thunderbird | Apr 29, 2026 | Apr 27, 2026 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade firefox | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade firefox-debuginfoUpgrade firefoxUpgrade firefox-debugsource | May 19, 2026 | Apr 21, 2026 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Apr 23, 2026 | Apr 23, 2026 |
| Freebsd | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-esr | Apr 30, 2026 | Apr 28, 2026 |
| Mfsa2026 30 | — | Upgrade to Mozilla Firefox version 150.0 | Apr 23, 2026 | Apr 21, 2026 |
| Mfsa2026 32 | — | Upgrade to Mozilla Firefox ESR version 140.10 | Apr 23, 2026 | Apr 21, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 140.10 | Apr 23, 2026 | Apr 21, 2026 |
| Oracle_linux | — | Upgrade firefoxUpgrade firefox-x11Upgrade thunderbird | Apr 29, 2026 | Apr 21, 2026 |
| Redhat_linux | — | Upgrade thunderbird-debugsourceUpgrade firefox-debuginfoUpgrade firefox-x11No solution existsUpgrade firefoxUpgrade thunderbird-debuginfoUpgrade thunderbirdUpgrade firefox-debugsource | Apr 29, 2026 | Apr 21, 2026 |
| Rocky_linux | — | Upgrade firefox-x11Upgrade firefox-debugsourceUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade thunderbirdUpgrade firefox-debuginfoUpgrade firefox | May 4, 2026 | Apr 28, 2026 |
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