CVE-2026-74986

Site isolation issue in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1...

CVE-2026-74986 Site isolation issue in the CSS Parsing and Computation component

Site isolation issue in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1...

CVE-2026-74986

Mozilla Firefox's CSS Parsing and Computation component has a site isolation flaw that could allow cross-origin data leakage. The issue is fixed in Firefox 154 and Firefox ESR 153.1; affected versions should upgrade immediately. No exploitation details are provided in the documents.