CVE-2026-6759: Vulnerability in Mozilla Firefox
Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the Widget: Cocoa component of 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 other unintended behavior. Mozilla fixed this issue in Firefox 150 and Firefox ESR 140.10. The vulnerability was reported by Steven Michaud and is classified with moderate impact by Mozilla. The fix is included in official Mozilla security advisories MFSA 2026-30 and MFSA 2026-32.
Potential Impact
The vulnerability could allow an attacker to cause memory corruption through use-after-free in the Widget: Cocoa component, which may lead to application instability or potential exploitation. However, the impact is rated moderate by Mozilla, and there are no known exploits in the wild. The fix prevents any such exploitation by addressing the memory safety issue.
Mitigation Recommendations
Mozilla has released official patches fixing this vulnerability in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, remediation depends on applying these updates. Patch status is confirmed by Mozilla advisories MFSA 2026-30 and MFSA 2026-32.
CVE-2026-6759: Vulnerability in Mozilla Firefox
Description
Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the Widget: Cocoa component of 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 other unintended behavior. Mozilla fixed this issue in Firefox 150 and Firefox ESR 140.10. The vulnerability was reported by Steven Michaud and is classified with moderate impact by Mozilla. The fix is included in official Mozilla security advisories MFSA 2026-30 and MFSA 2026-32.
Potential Impact
The vulnerability could allow an attacker to cause memory corruption through use-after-free in the Widget: Cocoa component, which may lead to application instability or potential exploitation. However, the impact is rated moderate by Mozilla, and there are no known exploits in the wild. The fix prevents any such exploitation by addressing the memory safety issue.
Mitigation Recommendations
Mozilla has released official patches fixing this vulnerability in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, remediation depends on applying these updates. Patch status is confirmed by Mozilla advisories MFSA 2026-30 and MFSA 2026-32.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-04-21T12:40:54.035Z
- 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/mfsa2026-32/","vendor":"Mozilla"}]
Threat ID: 69e7789c19fe3cd2cdd163da
Added to database: 4/21/2026, 1:16:12 PM
Last enriched: 4/21/2026, 1:46:19 PM
Last updated: 4/22/2026, 6:05:56 AM
Views: 9
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