CVE-2026-8947: Vulnerability in Mozilla Firefox
Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI Analysis
Technical Summary
CVE-2026-8947 is a use-after-free vulnerability affecting the DOM Bindings (WebIDL) component in Mozilla Firefox and related products. This memory corruption flaw could potentially allow an attacker to execute arbitrary code or cause a denial of service. The issue was fixed in Firefox 151 and corresponding ESR and Thunderbird versions. The vulnerability has a CVSS 3.1 base score of 7.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L), indicating network attack vector, low attack complexity, no privileges or user interaction required, and impacts on confidentiality, integrity, and availability. Mozilla has published multiple security advisories detailing this and related memory safety fixes.
Potential Impact
The vulnerability allows remote attackers to exploit a use-after-free condition in the DOM Bindings component, potentially leading to arbitrary code execution or denial of service. The CVSS score of 7.3 reflects high impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported at the time of disclosure.
Mitigation Recommendations
A fix for this vulnerability is available. Users and administrators should update affected Mozilla products to Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, or Thunderbird 140.11 or later. Applying these official updates fully mitigates the vulnerability. Patch status is confirmed by Mozilla security advisories MFSA 2026-46 and MFSA 2026-47.
CVE-2026-8947: Vulnerability in Mozilla Firefox
Description
Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVSS v3.1
Score 7.3high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-8947 is a use-after-free vulnerability affecting the DOM Bindings (WebIDL) component in Mozilla Firefox and related products. This memory corruption flaw could potentially allow an attacker to execute arbitrary code or cause a denial of service. The issue was fixed in Firefox 151 and corresponding ESR and Thunderbird versions. The vulnerability has a CVSS 3.1 base score of 7.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L), indicating network attack vector, low attack complexity, no privileges or user interaction required, and impacts on confidentiality, integrity, and availability. Mozilla has published multiple security advisories detailing this and related memory safety fixes.
Potential Impact
The vulnerability allows remote attackers to exploit a use-after-free condition in the DOM Bindings component, potentially leading to arbitrary code execution or denial of service. The CVSS score of 7.3 reflects high impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported at the time of disclosure.
Mitigation Recommendations
A fix for this vulnerability is available. Users and administrators should update affected Mozilla products to Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, or Thunderbird 140.11 or later. Applying these official updates fully mitigates the vulnerability. Patch status is confirmed by Mozilla security advisories MFSA 2026-46 and MFSA 2026-47.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-19T12:29:37.072Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-46/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-47/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-48/","vendor":"Mozilla"}]
Threat ID: 6a0c6779ec166c07b0a9937f
Added to database: 05/19/2026, 13:36:57 UTC
Last enriched: 07/15/2026, 08:14:50 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 68
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