CVE-2026-12321

JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2032943	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-57/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-60/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-06-16 13:16

Updated : 2026-06-17 10:14

NVD link : CVE-2026-12321

Mitre link : CVE-2026-12321

CVE.ORG link : CVE-2026-12321

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-670

Always-Incorrect Control Flow Implementation

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