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. Use-after-free bugs occur when a program continues to use a pointer after the memory it points to has been freed, potentially leading to memory corruption or arbitrary code execution. This vulnerability was fixed in Firefox 151 and the corresponding ESR versions 115.36 and 140.11. The fix is part of a broader set of memory safety bug fixes released by Mozilla on May 19, 2026. The vendor advisories confirm the high impact of this vulnerability and provide patches in the stated versions.
Potential Impact
The vulnerability is classified as high impact due to the use-after-free nature, which can lead to memory corruption and potentially arbitrary code execution if exploited. However, there are no known exploits in the wild at the time of publication. The vulnerability affects Firefox desktop and ESR versions prior to the fixed releases.
Mitigation Recommendations
Mozilla has released official patches fixing CVE-2026-8947 in Firefox 151, Firefox ESR 115.36, and Firefox ESR 140.11. Users and administrators should update to these versions or later to remediate this vulnerability. Since the vendor advisory confirms the fix availability, applying these updates is the recommended and effective mitigation. No additional or temporary mitigations are indicated by the vendor.
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.
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. Use-after-free bugs occur when a program continues to use a pointer after the memory it points to has been freed, potentially leading to memory corruption or arbitrary code execution. This vulnerability was fixed in Firefox 151 and the corresponding ESR versions 115.36 and 140.11. The fix is part of a broader set of memory safety bug fixes released by Mozilla on May 19, 2026. The vendor advisories confirm the high impact of this vulnerability and provide patches in the stated versions.
Potential Impact
The vulnerability is classified as high impact due to the use-after-free nature, which can lead to memory corruption and potentially arbitrary code execution if exploited. However, there are no known exploits in the wild at the time of publication. The vulnerability affects Firefox desktop and ESR versions prior to the fixed releases.
Mitigation Recommendations
Mozilla has released official patches fixing CVE-2026-8947 in Firefox 151, Firefox ESR 115.36, and Firefox ESR 140.11. Users and administrators should update to these versions or later to remediate this vulnerability. Since the vendor advisory confirms the fix availability, applying these updates is the recommended and effective mitigation. No additional or temporary mitigations are indicated by the vendor.
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: 5/19/2026, 1:36:57 PM
Last enriched: 5/19/2026, 2:07:31 PM
Last updated: 5/20/2026, 6:15:50 PM
Views: 10
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