CVE-2026-8948

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

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2038803	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-8948
https://bugzilla.redhat.com/show_bug.cgi?id=2479850
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8948.json

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox:::::-:::*
	cpe:2.3:a:mozilla:thunderbird::::::::

History

14 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Elusión de la política del mismo origen en el DOM: Componente de red. Esta vulnerabilidad fue corregida en Firefox 151 y Thunderbird 151.

Information

Published : 2026-05-19 14:16

Updated : 2026-10-14 20:10

NVD link : CVE-2026-8948

Mitre link : CVE-2026-8948

CVE.ORG link : CVE-2026-8948

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-942

Permissive Cross-domain Security Policy with Untrusted Domains

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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