Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL 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 firefox-x11Upgrade thunderbirdUpgrade firefox | Oct 11, 2026 | Sep 21, 2026 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Sep 21, 2026 | Sep 15, 2026 |
| Mfsa2026 90 | — | Upgrade to Mozilla Firefox version 156.0Upgrade to the latest version of Mozilla Firefox | 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 |
| Redhat_linux | — | Upgrade thunderbird-debuginfoNo solution existsUpgrade firefoxUpgrade firefox-x11Upgrade thunderbirdUpgrade firefox-debugsourceUpgrade thunderbird-debugsourceUpgrade firefox-debuginfo | Sep 18, 2026 | Sep 15, 2026 |
| Rocky_linux | — | Upgrade firefox-x11Upgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade firefox-debuginfoUpgrade thunderbirdUpgrade firefox-debugsourceUpgrade firefox | Sep 28, 2026 | Sep 26, 2026 |
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