cve 2026 20859

CVE-2026-20859 is a Windows kernel-mode driver elevation of privilege vulnerability recorded by Microsoft's Security Response Center. Administrators should treat it as a high-priority operational risk, confirming exact build mappings and deploying vendor fixes promptly. The public advisory establishes the CVE record and confidence metric but withholds low-level exploit mechanics. Defenders must combine rapid patching, targeted detection, and cautious threat modeling while researchers analyze the patch diff and any public proof-of-concept. This tag covers discussion of the vulnerability, its risk assessment, and recommended mitigation steps for Windows systems.