Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
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 |
|---|---|---|---|---|
| Amazon_linux_2023 | — | Upgrade firefox-debuginfoUpgrade firefoxUpgrade firefox-debugsource | Sep 1, 2026 | Aug 18, 2026 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Aug 20, 2026 | Aug 20, 2026 |
| Mfsa2026 74 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 154.0 | Aug 18, 2026 | Aug 18, 2026 |
| Mfsa2026 75 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 115.39 | Aug 18, 2026 | Aug 18, 2026 |
| Mfsa2026 76 | — | Upgrade to Mozilla Firefox ESR version 140.14Upgrade to the latest version of Mozilla Firefox | Aug 18, 2026 | Aug 18, 2026 |
| Mfsa2026 77 | — | Upgrade to Mozilla Firefox ESR version 153.1Upgrade to the latest version of Mozilla Firefox | Aug 18, 2026 | Aug 18, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 153.1Upgrade to the latest version of Mozilla Thunderbird | Aug 18, 2026 | Aug 18, 2026 |
| Redhat_linux | — | Upgrade firefoxUpgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade thunderbird-debugsourceUpgrade firefox-debugsourceUpgrade firefox-x11No solution existsUpgrade thunderbird | Aug 20, 2026 | Aug 18, 2026 |
| Rocky_linux | — | Upgrade thunderbirdUpgrade thunderbird-debugsourceUpgrade firefox-x11Upgrade thunderbird-debuginfoUpgrade firefox-debuginfoUpgrade firefoxUpgrade firefox-debugsource | Aug 26, 2026 | Aug 25, 2026 |
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