CVE-2023-28216
📋 TL;DR
This vulnerability allows an authenticated attacker to exploit a flaw in Windows Advanced Local Procedure Call (ALPC) to elevate privileges on a local system. It affects Windows operating systems and requires an attacker to have initial access to execute code. Successful exploitation could lead to SYSTEM-level privileges.
💻 Affected Systems
- Microsoft Windows
📦 What is this software?
Windows 10 1507 by Microsoft
Windows 10 1607 by Microsoft
Windows 10 1809 by Microsoft
Windows 10 20h2 by Microsoft
Windows 10 21h2 by Microsoft
Windows 10 22h2 by Microsoft
Windows 11 21h2 by Microsoft
Windows 11 22h2 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains SYSTEM privileges, enabling complete system compromise, credential theft, persistence establishment, and lateral movement within the network.
Likely Case
Local privilege escalation from a standard user account to SYSTEM or administrative privileges, allowing installation of malware, disabling security controls, or accessing sensitive data.
If Mitigated
With proper patch management and least privilege principles, impact is limited to isolated systems with minimal lateral movement potential.
🎯 Exploit Status
Exploitation requires local authenticated access and knowledge of the ALPC component. No public proof-of-concept has been released as of knowledge cutoff.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: April 2023 security updates (KB5025221 for Windows 10, KB5025239 for Windows 11, etc.)
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-28216
Restart Required: Yes
Instructions:
1. Apply April 2023 Windows security updates via Windows Update. 2. For enterprise environments, deploy updates through WSUS or SCCM. 3. Restart systems after patch installation.
🔧 Temporary Workarounds
No known workarounds
windowsMicrosoft has not published specific workarounds for this vulnerability
🧯 If You Can't Patch
- Implement strict least privilege principles to limit standard user capabilities
- Monitor for suspicious process creation and privilege escalation attempts using EDR solutions
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for April 2023 security updates or run 'systeminfo' command and verify OS build number is patched.Check Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify April 2023 security updates are installed via Windows Update history or check OS build numbers against Microsoft's security update documentation.📡 Detection & Monitoring
Log Indicators:
- Event ID 4688: A new process has been created with elevated privileges
- Event ID 4672: Special privileges assigned to new logon
- Suspicious ALPC-related process behavior
Network Indicators:
- No network indicators as this is a local privilege escalation
SIEM Query:
EventID=4688 AND NewProcessName="*" AND SubjectUserName!="SYSTEM" AND TokenElevationType="%%1938"