Privilege escalation in the WebExtensions 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.
CVSS Details
- CVSS 3.1 Base Score: 8.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade firefox-esrUpgrade thunderbird | 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 the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 153.3 | Sep 15, 2026 | Sep 15, 2026 |
| Redhat_linux | — | No solution exists | Sep 18, 2026 | Sep 15, 2026 |
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