Microsoft Patches Windows Privilege Escalation Flaws in CLFS Driver and Winlogon
Microsoft published security updates for multiple Windows local privilege escalation vulnerabilities, including CVE-2024-49138 in the Windows Common Log File System (CLFS) Driver and CVE-2024-30066 in Winlogon. Both issues could allow an attacker who already has access to a target system to elevate privileges, increasing the risk of full system compromise and follow-on activity such as credential theft, defense evasion, or lateral movement.
The advisories were released through Microsoft's Security Update Guide and identify the affected components as core parts of Windows used for logging and authentication workflows. Organizations running Windows systems should prioritize applying the relevant Microsoft patches, validate remediation across endpoints and servers, and monitor for signs of post-compromise privilege escalation involving clfs.sys, Winlogon, or other abnormal attempts to obtain elevated execution on patched and unpatched hosts.
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How this story unfolded
2 events from the most recent confirmed update back to the earliest known activity.
Microsoft publishes advisory for CVE-2024-49138
Microsoft added CVE-2024-49138, a Windows Common Log File System Driver Elevation of Privilege vulnerability, to its Security Update Guide. Two references describe the same publication and are treated as a single event.
Microsoft publishes advisory for CVE-2024-30066
Microsoft added CVE-2024-30066, a Winlogon Elevation of Privilege vulnerability, to its Security Update Guide. The reference indicates the advisory was published on June 11, 2024.
Sources
3 references tracked. Mallory keeps watching after this page renders.
CVE-2024-49138 - Security Update Guide - Microsoft - Windows Common Log File System Driver Elevation of Privilege Vulnerability
msrc.microsoft.com
Open sourceCVE-2024-49138 - Security Update Guide - Microsoft - Windows Common Log File System Driver Elevation of Privilege Vulnerability
msrc.microsoft.com
Open sourceCVE-2024-30066 - Security Update Guide - Microsoft - Winlogon Elevation of Privilege Vulnerability
msrc.microsoft.com
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