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.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Affected Vendors & Products

Vendors Products
Mozilla
  • Firefox
  • Thunderbird

Configuration 1 [-]

OR cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*

No data.

References
Link Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2016164 cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-6759 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-6759 cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-30/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-30/#CVE-2026-6759 cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-32/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-32/#CVE-2026-6759 cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-33/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-34/ cve-icon cve-icon
History

Wed, 22 Apr 2026 16:15:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla thunderbird
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
Vendors & Products Mozilla thunderbird

Wed, 22 Apr 2026 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

 ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 22 Apr 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-825
References
Metrics threat_severity

None

 threat_severity

Moderate

Wed, 22 Apr 2026 00:00:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150 and Firefox ESR 140.10. 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.
Weaknesses CWE-416
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Tue, 21 Apr 2026 18:00:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Vendors & Products Mozilla
Mozilla firefox

Tue, 21 Apr 2026 13:15:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150 and Firefox ESR 140.10.
Title Use-after-free in the Widget: Cocoa component
References
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-04-21T12:40:54.329Z

Updated: 2026-04-22T15:06:13.308Z

Reserved: 2026-04-21T12:40:54.035Z

Link: CVE-2026-6759

cve-icon Vulnrichment

Updated: 2026-04-21T17:48:33.083Z

cve-icon NVD

Status : Analyzed

Published: 2026-04-21T13:16:21.857

Modified: 2026-04-22T16:08:03.650

Link: CVE-2026-6759

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-21T12:40:54Z

Links: CVE-2026-6759 - Bugzilla