CVE-2026-20876

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{"analysis": {"en": {"generated_at": "2026-04-16T08:22:49.734979+00:00", "value": {"mitigation_remediation": ["Install the latest Windows update that fixes CVE-2026-20876 on all affected Windows 11 and Windows Server systems", "If the patch cannot be applied immediately, disable the VBS enclave feature on workloads that do not require it until remediation is possible", "Review and restrict local administrative accounts, removing unnecessary privileged users to reduce the window for an authorized attacker"], "summary": {"action": "Immediate Patch", "impact": "Local Privilege Escalation via VBS Enclave heap overflow"}, "threat_synthesis": {"affected_systems": "Affected Microsoft products include Windows 11 versions 22H3, 23H2, 24H2, and 25H2, as well as Microsoft Windows Server 2022 23H2 (Server Core), Windows Server 2025, and Windows Server 2025 Server Core installations. These versions run on both x64 and arm64 architectures.", "description_and_impact": "A heap-based buffer overflow in the Windows Virtualization-Based Security (VBS) enclave allows an attacker who already has local access to elevate privileges. The flaw enables the attacker to corrupt memory within the enclave runtime and execute arbitrary code with higher privilege levels, potentially compromising system integrity and confidentiality.", "risk_and_exploitability": "The CVSS score is 6.7, indicating medium severity, while the EPSS score is below 1%, suggesting a low probability of exploitation under current conditions. The vulnerability is not listed in the CISA KEV catalog. Attackers need local authorization to trigger the heap overflow, implying that prevention hinges on limiting local privileged access and applying the vendor patch as soon as feasible."}}}}, "created": "2026-04-16T08:30:29.833867+00:00", "updated": "2026-04-16T08:30:29.833884+00:00", "vendors": []}