CVE-2026-84126

Incorrect boundary conditions in the Layout: Grid component. This vulnerability was fixed in Firefox 155 and Thunderbird 155.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2063893	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-82/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-86/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-09-01 13:20

Updated : 2026-09-03 13:04

NVD link : CVE-2026-84126

Mitre link : CVE-2026-84126

CVE.ORG link : CVE-2026-84126

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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