DOM Navigation Component Vulnerability in Firefox by Mozilla
CVE-2026-100830

8.1HIGH

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
29 September 2026

What is CVE-2026-100830?

A mitigation bypass vulnerability has been identified in the DOM Navigation component of Firefox, allowing attackers to exploit certain navigational functionalities. This issue is particularly concerning as it may enable unauthorized access or manipulation of user navigations. The vulnerability affects specific versions of Firefox, prompting swift action to address the issue in newer releases, including Firefox ESR 153.4 and Firefox 157. Users are advised to upgrade to the latest versions to ensure they are protected against potential exploits.

Affected Version(s)

Firefox 153.4

Firefox 157

Thunderbird 153.4

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2066770
https://www.mozilla.org/security/advisories/mfsa2026-100/
https://www.mozilla.org/security/advisories/mfsa2026-101/

CVSS V3.1

Score:
8.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Finn Westendorf
.