Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Thunderbird 154, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 140.15, and Thunderbird 153.2.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade firefoxUpgrade thunderbirdUpgrade firefox-x11 | Oct 11, 2026 | Sep 14, 2026 |
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | Sep 21, 2026 | Aug 18, 2026 |
| Mfsa2026 83 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 115.40 | Sep 1, 2026 | Sep 1, 2026 |
| Mfsa2026 84 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 140.15 | Sep 1, 2026 | Sep 1, 2026 |
| Mfsa2026 85 | — | Upgrade to Mozilla Firefox ESR version 153.2Upgrade to the latest version of Mozilla Firefox | Sep 1, 2026 | Sep 1, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 153.2Upgrade to the latest version of Mozilla Thunderbird | Sep 1, 2026 | Sep 1, 2026 |
| Redhat_linux | — | Upgrade firefox-debugsourceUpgrade firefoxNo solution existsUpgrade firefox-x11Upgrade firefox-debuginfoUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade thunderbird | Sep 10, 2026 | Aug 18, 2026 |
| Rocky_linux | — | Upgrade firefoxUpgrade thunderbirdUpgrade firefox-debuginfoUpgrade thunderbird-debugsourceUpgrade firefox-debugsourceUpgrade thunderbird-debuginfoUpgrade firefox-x11 | Sep 28, 2026 | Sep 25, 2026 |
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