CVE-2026-109779: Vulnerability in Mozilla Firefox
Description
Race condition in the Networking: DNS component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
CVSS v3.1
Score 4.2medium
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-109779 is a race condition vulnerability affecting the Networking: DNS component in Mozilla Firefox. The issue could potentially allow unexpected behavior due to concurrent operations in DNS handling. Mozilla fixed this vulnerability in Firefox version 158.
Potential Impact
The vulnerability could lead to unpredictable behavior in the DNS networking component of Firefox, which might affect the stability or security of DNS resolution within the browser. No known exploits in the wild have been reported.
Mitigation Recommendations
Users should update Mozilla Firefox to version 158 or later to remediate this vulnerability. Since the fix is available, applying the official update fully mitigates the risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:49:13.115Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"}]
Threat ID: 6ace2c512cdf04f65661d579
Added to database: 10/13/2026, 13:04:17 UTC
Last enriched: 10/13/2026, 13:18:57 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 7
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