CVE-2026-109751: Vulnerability in Mozilla Firefox
Description
Information disclosure in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
CVSS v3.1
Score 4.3medium
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
pkg:github/mozilla/firefox-esrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves information disclosure within the Networking component of Mozilla Firefox. It was publicly disclosed and subsequently fixed in Firefox 158 and Firefox ESR 153.5. The vendor advisory URLs provide official confirmation of the fix and additional details.
Potential Impact
The vulnerability could allow unauthorized disclosure of information through the Networking component. There are no reports of active exploitation in the wild, indicating limited immediate risk. However, unpatched versions remain vulnerable to potential information leakage.
Mitigation Recommendations
Users should upgrade to Firefox 158 or later, or Firefox ESR 153.5 or later, where this vulnerability has been fixed. No additional mitigation steps are indicated by the vendor advisories.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:56.187Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","vendor":"Mozilla"}]
Threat ID: 6ace2c4b2cdf04f65661d54e
Added to database: 10/13/2026, 13:04:11 UTC
Last enriched: 10/13/2026, 13:48:14 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 4
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