CVE-2026-109734

8.1High

Published 13 Oct 2026 · NVD status: Deferred · AI triage by gemini-3.8-flash

8.1High

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required
Impact: High impact on confidentiality, integrity
Weakness: CWE-693

Impact

Remote attackers can bypass DOM security controls and compromise data integrity or confidentiality if a user visits a malicious page or views a malicious email. It requires user interaction such as opening a crafted link or message.

Root cause

A security mitigation bypass flaw exists within the DOM: Security component.

Affected systems

Firefox versions prior to 158, Firefox ESR versions prior to 153.5, Thunderbird versions prior to 158, and Thunderbird ESR versions prior to 153.5.

CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Fix & remediation

Upgrade to Firefox 158, Firefox ESR 153.5, Thunderbird 158, or Thunderbird 153.5. No interim mitigation is documented, so applying the package update is required.

shell

$ sudo apt-get update && sudo apt-get install --only-upgrade firefox thunderbird

AI-suggested. Run it in staging first and check it against the vendor advisory. Why?

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NVD description

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

References

Source: nvd.nist.gov/vuln/detail/CVE-2026-109734