CVE-2026-109742: Vulnerability in Mozilla Firefox
Description
Information disclosure in the PDF Viewer 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
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves information disclosure within the PDF Viewer component of Mozilla Firefox. The flaw could potentially allow unauthorized access to information through the PDF Viewer. Mozilla fixed this vulnerability in Firefox 158 and Firefox ESR 153.5, as documented in their security advisories MFSA2026-106 and MFSA2026-108.
Potential Impact
The impact of this vulnerability is limited to information disclosure. There are no reports of active exploitation. The vulnerability could allow an attacker to gain access to information that should otherwise be protected within the PDF Viewer component.
Mitigation Recommendations
Users should update to Firefox 158 or later, or Firefox ESR 153.5 or later, to remediate this vulnerability. Since official fixes are available, applying these updates is the recommended mitigation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:47.751Z
- 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: 6ace2c4b2cdf04f65661d545
Added to database: 10/13/2026, 13:04:11 UTC
Last enriched: 10/13/2026, 13:48:49 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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