CVE-2026-21218 — HIGH (7.5)

Q: What is CVE-2026-21218?

CVE-2026-21218 is a vulnerability with a CVSS score of 7.5 (HIGH). Improper handling of missing special element in .NET allows an unauthorized attacker to perform spoofing over a network.

Q: How severe is CVE-2026-21218?

CVE-2026-21218 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2026-21218?

Check the references section above for vendor advisories and patch information. Affected products include: Microsoft .Net, Apple Macos, Linux Linux Kernel, Microsoft Windows.

Vulnerability Description

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

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

HIGH

Availability

NONE

Affected Products

Vendor	Product	Versions
Microsoft	.Net	>= 8.0.0, < 8.0.24
Apple	Macos	-
Linux	Linux Kernel	-
Microsoft	Windows	-

Related Weaknesses (CWE)

CWE-166

References

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

FAQ

What is CVE-2026-21218?

CVE-2026-21218 is a vulnerability with a CVSS score of 7.5 (HIGH). Improper handling of missing special element in .NET allows an unauthorized attacker to perform spoofing over a network.

How severe is CVE-2026-21218?

CVE-2026-21218 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-21218?

Check the references section above for vendor advisories and patch information. Affected products include: Microsoft .Net, Apple Macos, Linux Linux Kernel, Microsoft Windows.