CVE-2026-109761: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
CVSS v3.1
Score 5.4medium
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-109761 describes a use-after-free vulnerability in the JavaScript WebAssembly component of Mozilla Firefox. This type of vulnerability can lead to memory corruption. The flaw was resolved by Mozilla in Firefox version 158.
Potential Impact
The vulnerability could potentially allow attackers to cause memory corruption via the WebAssembly component in Firefox. However, no known exploits in the wild have been reported.
Mitigation Recommendations
Users should update to Firefox version 158 or later, where this vulnerability has been fixed. No additional mitigation steps are required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:48:27.874Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"}]
Threat ID: 6ace2c4d2cdf04f65661d55c
Added to database: 10/13/2026, 13:04:13 UTC
Last enriched: 10/13/2026, 13:34:23 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 8
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