CVE-2026-4701

Use-after-free in the JavaScript Engine component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2009303	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-20/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-22/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-23/
https://www.mozilla.org/security/advisories/mfsa2026-24/

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-03-24 13:16

Updated : 2026-03-26 14:16

NVD link : CVE-2026-4701

Mitre link : CVE-2026-4701

CVE.ORG link : CVE-2026-4701

JSON object : View

Products Affected

mozilla

firefox

CWE

CWE-416

Use After Free

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