CVE-2026-109720: Vulnerability in Mozilla Firefox
Description
JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-109720 is a vulnerability involving JIT miscompilation within the JavaScript WebAssembly component of Mozilla Firefox. The issue could lead to incorrect code generation during runtime. 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 vulnerability could cause incorrect execution of WebAssembly code due to JIT miscompilation, potentially leading to unexpected behavior or security issues. However, no known exploits in the wild have been reported, and the vendor has released fixes.
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
- 2026-10-13T00:29:27.996Z
- 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: 6ace2c432cdf04f65661d4d6
Added to database: 10/13/2026, 13:04:03 UTC
Last enriched: 10/13/2026, 14:18:43 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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