CVE-2026-109717: Vulnerability in Mozilla Firefox
Description
Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
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
This vulnerability involves a use-after-free condition within the DOM Bindings (WebIDL) component of Mozilla Firefox. Use-after-free bugs can lead to memory corruption, potentially allowing attackers to execute arbitrary code or cause a crash. Mozilla has fixed this issue in Firefox 158 and Firefox ESR 153.5, as documented in their security advisories MFSA2026-106 and MFSA2026-108.
Potential Impact
If exploited, this vulnerability could allow an attacker to execute arbitrary code or cause a denial of service by triggering memory corruption. However, no active exploitation has been reported.
Mitigation Recommendations
Users should update to Firefox 158 or later, or Firefox ESR 153.5 or later, to ensure this vulnerability is patched. Since official fixes are available, applying these updates fully mitigates the risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:24.984Z
- 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: 6ace2c432cdf04f65661d4d3
Added to database: 10/13/2026, 13:04:03 UTC
Last enriched: 10/13/2026, 14:18:56 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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