CVE-2026-2783

Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2010943	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-13/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-15/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-16/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-17/	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

No history.

Information

Published : 2026-02-24 14:16

Updated : 2026-06-17 10:31

NVD link : CVE-2026-2783

Mitre link : CVE-2026-2783

CVE.ORG link : CVE-2026-2783

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-843

Access of Resource Using Incompatible Type ('Type Confusion')

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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