CVE-2026-109718: Vulnerability in Mozilla Firefox
Description
Use-after-free in the XML component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, 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 in the XML component of Mozilla Firefox, which could potentially lead to memory corruption or other unintended behavior. Mozilla has released fixes for this issue in Firefox 158, Firefox ESR 115.43, and Firefox ESR 153.5. The vendor advisories provide official confirmation of the fix.
Potential Impact
If exploited, the use-after-free vulnerability could allow an attacker to cause a crash or potentially execute arbitrary code. However, there are no reports of active exploitation in the wild.
Mitigation Recommendations
Users should update to Firefox 158, Firefox ESR 115.43, or Firefox ESR 153.5 or later to remediate this vulnerability. Applying these official fixes fully addresses the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:26.328Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-107/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","vendor":"Mozilla"}]
Threat ID: 6ace2c432cdf04f65661d4d4
Added to database: 10/13/2026, 13:04:03 UTC
Last enriched: 10/13/2026, 14:18:51 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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