CVE-2026-8948CWE-79CWE-942cross-site-scripting

CVE-2026-8948

Critical · published May 19, 2026

CVSS v3.1
9.1
EPSS
0%
Percentile
38.3
In the wild
Unconfirmed
What it is

Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00452 · 38.3th percentile
Weaknesses
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'); CWE-942 · Permissive Cross-domain Security Policy with Untrusted Domains
Published
2026-05-19T18:16Z
Affected products (2)
ProductVersionsFixed in
mozilla/firefox< 151.0.0151.0.0
mozilla/thunderbird< 151.0.0151.0.0
References (6)
https://bugzilla.mozilla.org/show_bug.cgi?id=2038803 · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-46/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-50/ · [email protected]https://access.redhat.com/security/cve/CVE-2026-8948 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://bugzilla.redhat.com/show_bug.cgi?id=2479850 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8948.json · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
EPSS history
Timeline
  • 19 MAY 12:29Z
    Same-origin policy bypass in the DOM: Networking component
    cvelistv5