CVE-2026-109779

4.2Medium

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

4.2Medium

Attack vector: Network
Complexity: High
Privileges needed: None
User interaction: Required
Impact: Limited impact
Weakness: CWE-362

Impact

Remote attackers can potentially cause limited integrity and confidentiality impacts if a user is tricked into interacting with malicious content. Exploitation depends on winning a race condition over the network.

Root cause

A race condition occurs within the Networking: DNS resolution component.

Affected systems

Firefox versions prior to 158 and Thunderbird versions prior to 158.

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

Fix & remediation

Upgrade Firefox and Thunderbird to version 158 or later. No interim workaround is documented.

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

Race condition in the Networking: DNS component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

References

Source: nvd.nist.gov/vuln/detail/CVE-2026-109779