CVE-2026-6746: Vulnerability in Mozilla Firefox
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
AI Analysis
Technical Summary
CVE-2026-6746 is a use-after-free vulnerability affecting the DOM: Core & HTML 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. Mozilla fixed this vulnerability in Firefox 150 and the corresponding ESR versions 115.35 and 140.10. The vendor advisory categorizes the impact as high and confirms the availability of patches. No public exploit activity has been reported.
Potential Impact
The vulnerability can cause memory corruption due to use-after-free in the DOM: Core & HTML component, which could potentially be exploited to execute arbitrary code or cause a crash. Mozilla rates the impact as high. There are no known exploits in the wild currently.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 150, Firefox ESR 115.35, and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the vulnerability. Since the vulnerability is patched, no additional mitigation steps are required.
CVE-2026-6746: Vulnerability in Mozilla Firefox
Description
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-6746 is a use-after-free vulnerability affecting the DOM: Core & HTML 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. Mozilla fixed this vulnerability in Firefox 150 and the corresponding ESR versions 115.35 and 140.10. The vendor advisory categorizes the impact as high and confirms the availability of patches. No public exploit activity has been reported.
Potential Impact
The vulnerability can cause memory corruption due to use-after-free in the DOM: Core & HTML component, which could potentially be exploited to execute arbitrary code or cause a crash. Mozilla rates the impact as high. There are no known exploits in the wild currently.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 150, Firefox ESR 115.35, and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the vulnerability. Since the vulnerability is patched, no additional mitigation steps are required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-04-21T12:40:43.779Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-30/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-31/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-32/","vendor":"Mozilla"}]
Threat ID: 69e7789819fe3cd2cdd16241
Added to database: 4/21/2026, 1:16:08 PM
Last enriched: 4/21/2026, 1:47:50 PM
Last updated: 4/22/2026, 7:18:04 AM
Views: 8
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