CVE-2026-12296

Severity CVSS v4.0:

Pending analysis

Type:

CWE-693 Protection Mechanism Failure

Publication date:

16/06/2026

Last modified:

15/07/2026

Description

Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 9.60 CRITICAL
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

9.60

Severity 3.x

CRITICAL

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:mozilla:firefox:::::esr:::*		140.12.0 (excluding)
cpe:2.3:a:mozilla:firefox:::::-:::*		152.0.0 (excluding)
cpe:2.3:a:mozilla:thunderbird:::::esr:::*		140.12.0 (excluding)
cpe:2.3:a:mozilla:thunderbird:::::-:::*		152.0.0 (excluding)

To consult the complete list of CPE names with products and versions, see this page

CVE-2026-12296

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools