CVE-2026-8948
Analyzed Analyzed - Analysis Complete
Same-origin policy bypass in Firefox DOM Networking

Publication date: 2026-05-19

Last updated on: 2026-05-20

Assigner: Mozilla Corporation

Description
Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-05-19
Last Modified
2026-05-20
Generated
2026-06-10
AI Q&A
2026-05-19
EPSS Evaluated
2026-06-08
NVD
CVE-2026-8948
EUVD
EUVD-2026-30900
Affected Vendors & Products
Showing 2 associated CPEs
Vendor Product Version / Range
mozilla firefox to 151.0.0 (exc)
mozilla thunderbird to 151.0.0 (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-942 The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability is a same-origin policy bypass in the DOM Networking component of Mozilla Firefox. The same-origin policy is a critical security mechanism that restricts how documents or scripts loaded from one origin can interact with resources from another origin. A bypass means that this restriction can be circumvented, potentially allowing malicious scripts to access or manipulate data from other origins.

This issue was fixed in Firefox version 151.

Impact Analysis

By bypassing the same-origin policy, an attacker could potentially access sensitive information or perform unauthorized actions by exploiting the DOM Networking component. This could lead to data leakage, unauthorized data manipulation, or other security breaches within the browser environment.

Mitigation Strategies

The vulnerability was fixed in Firefox 151. To mitigate this vulnerability, you should update your Firefox browser to version 151 or later.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-8948. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart