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{"analysis": {"en": {"generated_at": "2026-04-18T06:39:10.543134+00:00", "value": {"mitigation_remediation": ["Apply the Windows security update that resolves CVE\u20112026\u201120870 for all affected versions (24H2, 25H2, and Server\u202f2025).", "Reboot each system immediately after applying the update to ensure the kernel patch takes effect.", "If a patch cannot be deployed, isolate the affected systems from administrative networks and implement temporary controls to limit access to the Win32K ICOMP interface until a vendor fix is available."], "summary": {"action": "Patch immediately", "impact": "Local privilege escalation via use\u2011after\u2011free in the Win32K subsystem."}, "threat_synthesis": {"affected_systems": "Affected Microsoft products include Windows\u202f11 Version\u202f24H2, Windows\u202f11 Version\u202f25H2, Windows Server\u202f2025, and Windows Server\u202f2025 (Server Core). The CPE entries specify arm64 versions, indicating that arm64 builds are affected; it is inferred that x86\u201164 builds are also impacted, though this is not explicitly detailed in the supplier statement.", "description_and_impact": "The vulnerability is a use\u2011after\u2011free defect in the Windows\u202f11 Win32K kernel subsystem that is triggered when the ICOMP interface is accessed. A locally authenticated user can exploit the defect to execute arbitrary code in kernel mode, thereby gaining full control of the system. The flaw arises from incorrect handling of freed memory, allowing the attacker to override control data and run malicious code. This results in a loss of confidentiality, integrity, and availability for the affected machine.", "risk_and_exploitability": "The CVSS score of 7.8 classifies the issue as high severity. However, the EPSS score of less than one percent indicates a very low likelihood that the flaw will be exploited in the wild, and no entry is found in the CISA KEV catalog. The exploitation requires the attacker to have a legitimate local account and the ability to invoke the ICOMP interface. Once the use\u2011after\u2011free is triggered, kernel\u2011level execution is achieved, giving the attacker a full\u2011privilege compromise. Consequently, the risk for environments that expose the vulnerable interface remains high, but the probability of active exploitation is presently low."}}}}, "created": "2026-04-18T06:45:23.967541+00:00", "updated": "2026-04-18T06:45:23.967552+00:00", "vendors": []}