Use-after-free in the Widget: Cocoa component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

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 total

Affected Vendors & Products

Vendors Products
Mozilla
  • Firefox
  • Firefox Esr

Configuration 1 [-]

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

No data.

References
Link Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2017002 cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-4711 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-4711 cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-20/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-22/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-22/#CVE-2026-4711 cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-23/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-24/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-24/#CVE-2026-4711 cve-icon
History

Thu, 26 Mar 2026 00:15:00 +0000

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

None

 threat_severity

Moderate

Wed, 25 Mar 2026 17:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

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

Wed, 25 Mar 2026 12:00:00 +0000

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

Tue, 24 Mar 2026 20:30:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Widget: Cocoa component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. Use-after-free in the Widget: Cocoa component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
References

Tue, 24 Mar 2026 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Weaknesses CWE-416
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
Vendors & Products Mozilla
Mozilla firefox
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Tue, 24 Mar 2026 12:45:00 +0000

Type Values Removed Values Added
Description Use-after-free in the Widget: Cocoa component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.
Title Use-after-free in the Widget: Cocoa component
References
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-03-24T12:30:36.392Z

Updated: 2026-03-25T16:25:17.158Z

Reserved: 2026-03-23T23:22:23.818Z

Link: CVE-2026-4711

cve-icon Vulnrichment

Updated: 2026-03-25T16:24:53.783Z

cve-icon NVD

Status : Modified

Published: 2026-03-24T13:16:07.010

Modified: 2026-03-25T17:17:10.257

Link: CVE-2026-4711

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-03-24T12:30:36Z

Links: CVE-2026-4711 - Bugzilla