CVE-2026-42982 is a Windows Secure Kernel Mode elevation of privilege vulnerability caused by improper validation of consistency within input. Microsoft rates it as High severity with a CVSS v3.1 base score of 7.8 and temporal score of 6.8. The attack vector is local, requires low privileges, and no user interaction. If successfully exploited, an attacker could gain SYSTEM privileges. Microsoft reports no public disclosure and no known exploitation, with exploit code maturity marked unproven. Because this is a local privilege escalation issue, enterprise risk is primarily on systems where untrusted local users or code can run.

Highlights:
- CVSS scores: Base 7.8 - Temporal 6.8
- Exploit status & code maturity: Publicly Disclosed: No; Exploited: No; Exploit Code Maturity: UNPROVEN.
- Impact: Elevation of Privilege; confidentiality, integrity, and availability impacts are all HIGH. Successful exploitation could yield SYSTEM privileges.
- Exploitation likelihood: Exploitation Less Likely; vector context is LOCAL, LOW attack complexity, LOW privileges required, and NO user interaction.
- Severity for enterprise: High technical severity, but lower exposure than remote vulnerabilities because exploitation requires local access. Higher relevance on multi-user systems or hosts where untrusted local code can execute.
- Patch status: available; customer action required.

Affected systems:
- Windows 10 1607
- Windows 10 1809
- Windows 10 21H2
- Windows 10 22H2
- Windows 11 23H2
- Windows 11 24H2
- Windows 11 25H2
- Windows 11 26H1
- Windows 11 unspecified
- Windows Server 2016
- Windows Server 2019
- Windows Server 2022
- Windows Server 2025