CVE-2026-74960

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...

CVE-2026-74960 Site isolation issue in the WebExtensions component

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...

CVE-2026-74960

A site isolation flaw in Firefox's WebExtensions component could allow cross-site data access by extensions. Affected versions are pre-154 and pre-ESR 140.14/153.1; upgrading to those versions is the fix. No exploit details are provided in the documents.