CVE-2026-20818

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{"analysis": {"en": {"generated_at": "2026-04-18T06:42:18.908563+00:00", "value": {"mitigation_remediation": ["Apply the official Microsoft security update that addresses CVE-2026-20818.", "If the patch cannot yet be applied, reduce the permissions on the kernel log files so that only the system account or elevated privileged users can read them.", "Continuously monitor system logs for unusual or unauthorized read attempts to detect potential exploitation attempts."], "summary": {"action": "Apply Patch", "impact": "Local Information Disclosure"}, "threat_synthesis": {"affected_systems": "Affected systems include Microsoft Windows Server 2016, 2019, 2022, and 2025 in both full and Server Core installations, as well as the 23H2 edition of Windows Server 2022 and the 23H2 edition of Windows Server 2025. All variants listed in the CVE are impacted.", "description_and_impact": "The vulnerability arises from sensitive information being written to a kernel log file, allowing an unauthorized local attacker to read that data and thereby gain access to confidential information. This vulnerability is based on CWE-532, which concerns information exposure through log files. This results in a loss of confidentiality and potentially the exposure of credentials or configuration details that are not meant for user access.", "risk_and_exploitability": "The severity score is 6.2 on the CVSS scale, indicating a moderate impact. The EPSS score is less than 1%, reflecting a very low likelihood of widespread exploitation. The vulnerability is not currently cataloged in CISA\u2019s Known Exploited Vulnerabilities list. Because it requires an attacker to have local access, the attack vector is local; an attacker would need to run code or have a user context that can read the kernel log file to extract the disclosed data."}}}}, "created": "2026-04-18T06:45:23.969499+00:00", "updated": "2026-04-18T06:45:23.969509+00:00", "vendors": []}