CVE-2026-109779: Race condition in the Networking: DNS component

Published Oct 13, 2026
·
Updated

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

Affected Software

2 affected componentsFixes available
Mozilla Firefox<158
158
Mozilla Thunderbird<158
158

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 158
  2. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 158

Event History

Oct 13, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·12:29 PM
Data Sourced
via MITRE·12:29 PM
Description
Data Sourced
via NVD·01:17 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What conditions are required for exploitation?

The CVSS vector indicates exploitation is network-based but has high attack complexity and requires user interaction. No privileges are required, and successful exploitation can result in limited confidentiality and integrity impact.

2

Which Firefox versions are affected?

The provided data states that the vulnerability was fixed in Firefox 158. It does not identify the first affected version or a complete affected-version range.

3

Are availability impacts expected?

No. The CVSS vector assigns no availability impact, while confidentiality and integrity impacts are rated low.

Company

Resources

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