Description
Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Affected products
mozilla: firefox; mozilla: thunderbird
References6
- www.mozilla.org/security/advisories/mfsa2026-46/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-50/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2038803 Permissions Required
- access.redhat.com/security/cve/CVE-2026-8948
- bugzilla.redhat.com/show_bug.cgi?id=2479850
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8948.…
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 14 November 2026
- CWE
- CWE-942CWE-79
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