Site Isolation Vulnerability in Firefox Networking Component
CVE-2026-124913

Currently unrated

Key Information:

Vendor: Mozilla
Status: Firefox
Vendor: CVE Published:; 10 November 2026

What is CVE-2026-124913?

A site isolation vulnerability has been identified in the Networking component of Firefox, potentially allowing unauthorized access to sensitive data across web sessions. This issue was rectified in Firefox version 160 and Firefox ESR version 153.7, highlighting the importance of timely updates to maintain user security.

Affected Version(s)

Firefox 153.7

Firefox 160

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2045704

https://www.mozilla.org/security/advisories/mfsa2026-125/

https://www.mozilla.org/security/advisories/mfsa2026-127/

Download the Critical Vulnerability Management Cheat Sheet

Timeline

Vulnerability published
Nov 10, 2026
Vulnerability Reserved
Nov 9, 2026

Credit

Mozilla

CVE-2026-124913 Data

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