CVE-2026-21218

Improper handling of missing special element in .NET allows an unauthorized attacker to perform spoofing over a network.

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 NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21218	Vendor Advisory

Configurations

Configuration 1 (hide)

AND

OR	cpe:2.3:a:microsoft:.net::::::::
	cpe:2.3:a:microsoft:.net::::::::
	cpe:2.3:a:microsoft:.net::::::::

OR	cpe:2.3:o:apple:macos:-:::::::*
	cpe:2.3:o:linux:linux_kernel:-:::::::*
	cpe:2.3:o:microsoft:windows:-:::::::*

History

17 Jun 2026, 10:18

Type	Values Removed	Values Added
Summary		(es) Manejo inadecuado de un elemento especial faltante en .NET permite a un atacante no autorizado realizar suplantación de identidad a través de una red.

12 Feb 2026, 17:35

Type	Values Removed	Values Added
First Time		Linux Microsoft Microsoft windows Apple macos Apple Microsoft .net Linux linux Kernel
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21218 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21218 - Vendor Advisory
CPE		cpe:2.3:o:microsoft:windows:-:::::::* cpe:2.3:a:microsoft:.net:::::::: cpe:2.3:o:apple:macos:-:::::::* cpe:2.3:o:linux:linux_kernel:-:::::::*

10 Feb 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-10 18:16

Updated : 2026-06-17 10:18

NVD link : CVE-2026-21218

Mitre link : CVE-2026-21218

CVE.ORG link : CVE-2026-21218

JSON object : View

Products Affected

microsoft

.net
windows

apple

macos

linux

linux_kernel

CWE

CWE-166

Improper Handling of Missing Special Element

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