ByteOS Network

NVD Vulnerability Details :

CVE-2026-8959

Undergoing Analysis

Source-security@mozilla.org

Published At-19 May, 2026 | 14:16

Updated At-19 May, 2026 | 18:16

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.

Date Added	Due Date	Vulnerability Name	Required Action
	N/A

Metrics

Type	Version	Base score	Base severity	Vector
Secondary	3.1	9.6	CRITICAL	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Type: Secondary

Version: 3.1

Base score: 9.6

Base severity: CRITICAL

Vector:

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Weaknesses

CWE ID	Type	Source
CWE-20	Secondary	134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-119	Secondary	134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-693	Secondary	134c704f-9b21-4f2e-91b3-4a467353bcc0

CWE ID: CWE-20

Type: Secondary

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

CWE ID: CWE-119

Type: Secondary

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

CWE ID: CWE-693

Type: Secondary

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

References

Hyperlink	Source	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2034754	security@mozilla.org	N/A
https://www.mozilla.org/security/advisories/mfsa2026-46/	security@mozilla.org	N/A
https://www.mozilla.org/security/advisories/mfsa2026-48/	security@mozilla.org	N/A
https://www.mozilla.org/security/advisories/mfsa2026-50/	security@mozilla.org	N/A
https://www.mozilla.org/security/advisories/mfsa2026-51/	security@mozilla.org	N/A