Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
History

Tue, 19 May 2026 18:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-120

Tue, 19 May 2026 17:45:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11. Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
References

Tue, 19 May 2026 17:15:00 +0000

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

Tue, 19 May 2026 16:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-119
CWE-693
Metrics cvssV3_1

{'score': 9.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H'}

ssvc

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


Tue, 19 May 2026 15:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-120
CWE-20

Tue, 19 May 2026 13:45:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.
Title Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component
References

cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-05-19T17:10:50.516Z

Reserved: 2026-05-19T12:29:54.802Z

Link: CVE-2026-8959

cve-icon Vulnrichment

Updated: 2026-05-19T16:07:03.195Z

cve-icon NVD

Status : Undergoing Analysis

Published: 2026-05-19T14:16:52.280

Modified: 2026-05-19T18:16:34.907

Link: CVE-2026-8959

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-19T19:30:12Z