CVE-2026-74960 (GCVE-0-2026-74960)
Vulnerability from cvelistv5
Published
2026-08-18 12:23
Modified
2026-08-21 20:00
Severity ?
8.1 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Summary
Site isolation issue in the WebExtensions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140.14
Unaffected: 153.1
Unaffected: 154
 Create a notification for this product.
   Mozilla Thunderbird Unaffected: 140.14
Unaffected: 153.1
Unaffected: 154
 Create a notification for this product.
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