CVE-2020-0668: Windows 10 Privilege Escalation Flaw

CVE-2020-0668 Overview

An elevation of privilege vulnerability exists in the way that the Windows Kernel handles objects in memory. This vulnerability, known as the 'Windows Kernel Elevation of Privilege Vulnerability', allows a local attacker with low privileges to escalate their access to gain complete control over the affected system. This CVE ID is unique from CVE-2020-0669, CVE-2020-0670, CVE-2020-0671, and CVE-2020-0672, indicating a broader pattern of memory handling issues within the Windows Kernel during this period.

Critical Impact

Local attackers can leverage this privilege escalation vulnerability to execute arbitrary code with SYSTEM privileges, potentially compromising the entire Windows operating system and all data on the affected machine.

Affected Products

• Microsoft Windows 10 (all versions including 1607, 1709, 1803, 1809, 1903, 1909)
• Microsoft Windows 7 SP1
• Microsoft Windows 8.1
• Microsoft Windows RT 8.1
• Microsoft Windows Server 2008 SP2 and R2 SP1
• Microsoft Windows Server 2012 and R2
• Microsoft Windows Server 2016 (including versions 1803, 1903, 1909)
• Microsoft Windows Server 2019

Discovery Timeline

• February 11, 2020 - CVE-2020-0668 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2020-0668

Vulnerability Analysis

This elevation of privilege vulnerability stems from improper object handling within the Windows Kernel's memory management subsystem. The vulnerability is classified under CWE-732 (Incorrect Permission Assignment for Critical Resource), indicating that the kernel fails to properly validate permissions when handling certain memory objects.

The attack requires local access to the target system and the attacker must already possess low-level privileges. However, once exploited, the vulnerability enables complete privilege escalation from a standard user account to SYSTEM-level access. This represents a significant security boundary bypass, as it allows attackers to break out of user-space restrictions and gain kernel-level control.

The vulnerability has been documented through multiple exploit techniques, including abuse of the Windows Service Tracing functionality. Security researchers have demonstrated that the flaw can be triggered through specific kernel object manipulation sequences that cause the kernel to mishandle object permissions during memory operations.

Root Cause

The root cause lies in incorrect permission assignment for critical kernel resources (CWE-732). The Windows Kernel improperly validates access permissions when handling memory objects, allowing low-privileged users to manipulate objects that should only be accessible to higher-privileged processes or the kernel itself. This permission validation failure creates an exploitable pathway for privilege escalation.

Attack Vector

The attack vector is local, requiring the attacker to have prior access to the target system with at least low-level user privileges. The exploitation flow typically involves:

1. An attacker with standard user access identifies a vulnerable Windows system
2. The attacker leverages the improper object handling to create a condition where kernel objects can be manipulated
3. Through careful memory manipulation, the attacker forces the kernel to grant elevated permissions
4. The attacker achieves SYSTEM-level privileges, gaining complete control over the operating system

Exploitation techniques documented in public resources demonstrate that the Service Tracing functionality can be abused as part of the attack chain. For detailed technical analysis, refer to the Zero Day Initiative Advisory ZDI-20-257 and the Packet Storm exploit documentation.

Detection Methods for CVE-2020-0668

Indicators of Compromise

• Unexpected processes running with SYSTEM privileges that originated from low-privileged user accounts
• Anomalous Service Tracing activity or modifications to tracing-related registry keys
• Unusual kernel object access patterns detected in Windows Security event logs
• Evidence of privilege escalation tools or scripts targeting Windows Kernel vulnerabilities

Detection Strategies

• Monitor Windows Security Event Log for Event ID 4688 (Process Creation) with anomalous parent-child process relationships indicating privilege escalation
• Deploy endpoint detection rules to identify known exploitation patterns associated with CVE-2020-0668 and related Service Tracing abuse
• Implement behavioral analysis to detect processes that suddenly gain elevated privileges without legitimate authorization workflows
• Use kernel-level monitoring tools to detect suspicious object manipulation sequences

Monitoring Recommendations

• Enable advanced Windows Security Auditing for process creation, privilege use, and object access events
• Configure SentinelOne Singularity XDR to monitor for kernel-level privilege escalation attempts and anomalous SYSTEM process spawning
• Establish baseline behavior for Service Tracing functionality to identify deviations that may indicate exploitation attempts
• Review Windows Event Logs regularly for signs of local privilege escalation activity

How to Mitigate CVE-2020-0668

Immediate Actions Required

• Apply the security updates provided by Microsoft in the February 2020 Patch Tuesday release immediately
• Prioritize patching systems with standard user access that may be targeted for privilege escalation attacks
• Audit systems for signs of prior exploitation, particularly looking for unauthorized SYSTEM-level processes
• Restrict local access to sensitive systems and implement the principle of least privilege for user accounts

Patch Information

Microsoft released security patches for CVE-2020-0668 as part of the February 2020 security update cycle. Organizations should apply the appropriate patches for their Windows versions as documented in the Microsoft Security Advisory CVE-2020-0668. The patch addresses the improper object handling in the Windows Kernel that enables the privilege escalation.

Workarounds

• Limit local user access on critical servers and workstations to reduce the attack surface for privilege escalation
• Implement application whitelisting to prevent execution of unauthorized privilege escalation tools
• Monitor and restrict modifications to Service Tracing configurations which have been identified as part of exploitation chains
• Deploy SentinelOne endpoint protection with kernel-level monitoring capabilities to detect and block exploitation attempts in real-time

# Verify patch installation status
wmic qfe list full | findstr /i "KB4537789 KB4537776 KB4537764"

# Check Windows Update history for February 2020 security updates
Get-HotFix | Where-Object {$_.InstalledOn -ge "2020-02-01"} | Format-Table -AutoSize