Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade firefoxUpgrade thunderbirdUpgrade firefox-x11 | Oct 11, 2026 | Sep 21, 2026 |
| Amazon Linux Ami 2 | — | Upgrade firefox | Oct 19, 2026 | Oct 19, 2026 |
| Amazon_linux_2023 | — | Upgrade firefoxUpgrade firefox-debugsourceUpgrade firefox-debuginfo | Oct 13, 2026 | Sep 15, 2026 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Sep 21, 2026 | Sep 15, 2026 |
| Mfsa2026 90 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 156.0 | Sep 15, 2026 | Sep 15, 2026 |
| Mfsa2026 91 | — | Upgrade to Mozilla Firefox ESR version 115.41Upgrade to the latest version of Mozilla Firefox | Sep 15, 2026 | Sep 15, 2026 |
| Mfsa2026 92 | — | Upgrade to Mozilla Firefox ESR version 140.16Upgrade to the latest version of Mozilla Firefox | Sep 15, 2026 | Sep 15, 2026 |
| Mfsa2026 93 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 153.3 | Sep 15, 2026 | Sep 15, 2026 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 153.3Upgrade to the latest version of Mozilla Thunderbird | Sep 15, 2026 | Sep 15, 2026 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-x11 | Oct 22, 2026 | Sep 15, 2026 |
| Redhat_linux | — | Upgrade firefox-debuginfoUpgrade firefox-debugsourceNo solution existsUpgrade firefox-x11Upgrade thunderbird-debuginfoUpgrade thunderbirdUpgrade thunderbird-debugsourceUpgrade firefox | Sep 18, 2026 | Sep 15, 2026 |
| Rocky_linux | — | Upgrade firefox-debuginfoUpgrade firefoxUpgrade thunderbird-debugsourceUpgrade thunderbirdUpgrade firefox-debugsourceUpgrade firefox-x11Upgrade thunderbird-debuginfo | Sep 28, 2026 | Sep 26, 2026 |
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