CVE-2022-22037: Windows 10 ALPC Privilege Escalation

CVE-2022-22037 Overview

CVE-2022-22037 is an Elevation of Privilege vulnerability in the Windows Advanced Local Procedure Call (ALPC) subsystem. ALPC is a high-performance inter-process communication (IPC) mechanism used extensively throughout Windows for communication between user-mode processes and kernel-mode components. This vulnerability allows an authenticated attacker to elevate their privileges on the affected system, potentially gaining SYSTEM-level access from a low-privileged user context.

Critical Impact

Successful exploitation could allow attackers to gain elevated privileges on Windows systems, enabling complete system compromise, lateral movement, and persistent access across the enterprise environment.

Affected Products

• Microsoft Windows 10 (all versions including 20H2, 21H1, 21H2, 1607, 1809)
• Microsoft Windows 11 (x64 and ARM64)
• 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 20H2)
• Microsoft Windows Server 2019
• Microsoft Windows Server 2022

Discovery Timeline

• July 12, 2022 - CVE-2022-22037 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2022-22037

Vulnerability Analysis

This elevation of privilege vulnerability exists within the Windows Advanced Local Procedure Call (ALPC) implementation. ALPC serves as the primary IPC mechanism in Windows, replacing the legacy Local Procedure Call (LPC) system. It facilitates communication between processes, including critical interactions between user-mode applications and kernel-mode services.

The vulnerability can be exploited over a network connection, though it requires the attacker to already have low-level privileges on the target system. The exploitation complexity is considered high, meaning successful attacks require specific conditions to be met or additional preparation by the attacker. Once exploited, the vulnerability can result in complete compromise of confidentiality, integrity, and availability of the affected system.

The widespread deployment of ALPC across virtually all Windows services means that a successful exploit could provide attackers with a reliable privilege escalation primitive, making this vulnerability particularly valuable in attack chains where initial access has already been achieved through other means.

Root Cause

The vulnerability stems from improper handling within the ALPC subsystem. While Microsoft has not disclosed specific technical details about the root cause, ALPC vulnerabilities typically involve issues such as improper validation of message structures, race conditions in port handling, or incorrect permission checks during cross-process communication. The ALPC subsystem operates at a privileged level to facilitate IPC, and flaws in its implementation can allow attackers to manipulate this trusted communication channel.

Attack Vector

The attack vector for CVE-2022-22037 involves network-based exploitation that requires the attacker to have low-level authenticated access to the target system. The attack path typically involves:

1. The attacker first gains low-privilege access to a Windows system through credential compromise or other initial access vectors
2. The attacker then crafts malicious ALPC messages or exploits the vulnerable code path in the ALPC subsystem
3. Due to the improper handling in ALPC, the attacker can escalate privileges beyond their intended access level
4. With elevated privileges, the attacker gains the ability to execute code in a higher security context, potentially achieving SYSTEM-level access

The exploitation does not require user interaction, meaning no victim participation (such as clicking links or opening files) is necessary once the attacker has initial authenticated access.

Detection Methods for CVE-2022-22037

Indicators of Compromise

• Unusual process creation events where low-privileged processes spawn high-privileged child processes
• Suspicious ALPC port connections from unexpected processes or services
• Anomalous system calls related to NtAlpcConnectPort, NtAlpcSendWaitReceivePort, or other ALPC-related APIs
• Process token manipulation events indicating privilege escalation attempts

Detection Strategies

• Deploy endpoint detection solutions capable of monitoring ALPC-related system calls and identifying anomalous patterns
• Implement behavioral detection rules to identify privilege escalation patterns, such as unexpected SYSTEM-level process spawning
• Monitor Windows Security Event logs for Event ID 4688 (Process Creation) with attention to parent-child process privilege relationships
• Utilize SentinelOne's behavioral AI engine to detect exploitation attempts targeting ALPC subsystem vulnerabilities

Monitoring Recommendations

• Enable advanced audit policies for process creation and privilege use events
• Configure alerting on LSASS (Local Security Authority Subsystem Service) access attempts from non-standard processes
• Implement network-level monitoring for lateral movement attempts following potential privilege escalation
• Deploy memory protection technologies to detect exploitation attempts targeting kernel-mode components

How to Mitigate CVE-2022-22037

Immediate Actions Required

• Apply the latest Windows security updates from Microsoft's July 2022 Patch Tuesday release immediately
• Prioritize patching for systems exposed to higher-risk network segments or those accessible from less trusted zones
• Ensure SentinelOne agents are deployed and updated across all Windows endpoints for runtime protection
• Review and restrict user privileges following the principle of least privilege to minimize the impact of privilege escalation vulnerabilities

Patch Information

Microsoft addressed this vulnerability as part of the July 2022 Patch Tuesday security updates. Organizations should apply the corresponding cumulative updates for their specific Windows versions. Detailed patch information and download links are available through the Microsoft Security Response Center advisory for CVE-2022-22037.

For enterprise deployments, use Windows Server Update Services (WSUS), Microsoft Endpoint Configuration Manager, or other patch management solutions to deploy updates systematically across the environment.

Workarounds

• Implement network segmentation to limit the blast radius of potential compromise, isolating high-value systems from general user networks
• Apply strict access controls and authentication requirements to limit which users can access sensitive systems
• Deploy application allowlisting to prevent unauthorized code execution even in elevated contexts
• Monitor for exploitation attempts using SentinelOne's Singularity platform while patches are being deployed

# Verify Windows Update status using PowerShell
Get-HotFix | Where-Object {$_.InstalledOn -gt (Get-Date).AddDays(-30)} | Sort-Object InstalledOn -Descending

# Check for pending updates
Get-WindowsUpdate -MicrosoftUpdate -Verbose

# Force Windows Update check
wuauclt /detectnow /updatenow