CVE-2026-109763

—Unscored

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

—Unscored

Attack vector: —
Complexity: —
Privileges needed: —
User interaction: —
Impact: —
Weakness: —

Impact

Attackers can bypass security mitigations via malicious files or user interaction. An attacker needs to convince a user to open an untrusted file or visit a malicious page.

Root cause

A mitigation bypass flaw exists within the File Handling component.

Affected systems

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

Fix & remediation

Upgrade to Firefox 158, Firefox ESR 153.5, Thunderbird 158, or Thunderbird 153.5. No interim mitigation is documented, so prioritize package updates.

shell

$ sudo apt-get update && sudo apt-get --only-upgrade install 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 File Handling 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-2026-109763