Critical Windows CLFS Driver Vulnerability Exposes Systems to Privilege Escalation (CVE-2020-18032)

A critical privilege escalation flaw in Windows operating systems exposes millions of devices to local attacks. Tracked as CVE-2020-18032, this vulnerability carries a CVSS v3.1 score of 7.8 (High severity). Attackers exploiting this flaw could gain complete system control.

Technical Analysis

The vulnerability resides in the Common Log File System (CLFS) driver. Improper handling of objects in memory creates a buffer overflow condition. Local attackers can execute arbitrary code with elevated SYSTEM privileges through crafted requests. This enables installation of malware, data theft, and full system compromise.

Affected versions include Windows 10 versions 1809 through 2004, Windows Server 2016, Windows Server 2019, and Windows Server version 1903. Unpatched systems allow attackers with basic user access to bypass security boundaries.

Mitigation Requirements

Microsoft addressed this vulnerability in the October 13, 2020 Patch Tuesday updates. All affected systems must install the latest security patches immediately. Enterprise administrators should prioritize deployment to servers and workstations.

Patch deployment methods:

• Windows Update: Automatic updates via Settings > Update & Security
• Microsoft Update Catalog: Manual download for specific KB packages
• Enterprise deployment: WSUS or System Center Configuration Manager

Verify patch installation using command prompt: systeminfo | find "KB4577668" (version-dependent KB numbers apply). Systems without October 2020 or later patches remain vulnerable to local privilege escalation attacks.

Timeline and Resources

• Vulnerability reported: August 2020
• Patch released: October 13, 2020
• Public disclosure: October 13, 2020

Reference Microsoft's Security Update Guide for technical details. Review Windows Update documentation for enterprise deployment procedures. Unpatched systems should be considered at immediate risk.