CVE-2026-8958

Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2034713	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-48/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-51/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

14 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Revelación de información, escape de sandbox en el componente Seguridad: Process Sandboxing. Esta vulnerabilidad se corrigió en Firefox 151, Firefox ESR 140.11, Thunderbird 151 y Thunderbird 140.11.

Information

Published : 2026-05-19 14:16

Updated : 2026-10-14 20:10

NVD link : CVE-2026-8958

Mitre link : CVE-2026-8958

CVE.ORG link : CVE-2026-8958

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-668

Exposure of Resource to Wrong Sphere

CWE-693

Protection Mechanism Failure

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