CVE-2022-23284: Windows Print Spooler Privilege Escalation

CVE-2022-23284 Overview

CVE-2022-23284 is an elevation of privilege vulnerability in the Windows Print Spooler service. Microsoft disclosed the issue as part of its March 2022 Patch Tuesday cycle. Successful exploitation allows an authenticated attacker to gain higher privileges on an affected Windows host. The flaw impacts a broad set of supported Windows desktop and server releases, including Windows 10, Windows 11, Windows 8.1, and Windows Server 2012 through 2022. Print Spooler (spoolsv.exe) runs as SYSTEM, making any logic flaw in this component a high-value target for local privilege escalation.

Critical Impact
An authenticated attacker can elevate to SYSTEM on affected Windows hosts, compromising the confidentiality, integrity, and availability of the operating system.

Affected Products

Microsoft Windows 10 (versions 1607, 1809, 1909, 20H2, 21H1, 21H2)
Microsoft Windows 11 (x64 and ARM64), Windows 8.1, and Windows RT 8.1
Microsoft Windows Server 2012, 2012 R2, 2016, 2019, 2022, and Server 20H2

Discovery Timeline

2022-03-09 - Microsoft publishes the advisory and ships a security patch
2022-03-09 - CVE-2022-23284 published to NVD
2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-23284

Vulnerability Analysis

The vulnerability resides in the Windows Print Spooler service, which manages print jobs, printer drivers, and printer configuration on Windows systems. Print Spooler runs with SYSTEM privileges and exposes interfaces accessible to local users and authenticated remote users. A flaw in how the service handles privileged operations enables an attacker with valid credentials to perform actions that should be restricted to administrators.

Microsoft classifies the issue as elevation of privilege rather than remote code execution. The CWE entry is marked NVD-CWE-noinfo, indicating Microsoft did not publicly attribute the root cause to a specific weakness category. The CVSS vector requires high privileges (PR:H) and no user interaction, with the attack traversing the network protocol surface exposed by the spooler.

Root Cause

The defect involves improper handling of privileged operations inside Print Spooler. Print Spooler has a history of CWE-269 (Improper Privilege Management) and CWE-427 (Uncontrolled Search Path) issues stemming from driver installation paths, file copy operations, and RPC interfaces. Microsoft has not published low-level technical details for CVE-2022-23284 beyond the advisory.

Attack Vector

An authenticated attacker interacts with the Print Spooler service over its exposed RPC interfaces. By issuing crafted spooler operations, the attacker triggers privileged behavior that executes in the context of SYSTEM. The exploit does not require user interaction. The EPSS score of 9.515% places this CVE in the 92nd percentile for predicted exploitation likelihood, indicating attacker interest in similar spooler defects.

No verified proof-of-concept code is publicly indexed for this CVE. Refer to the Microsoft Security Update Advisory for vendor-supplied detail.

Detection Methods for CVE-2022-23284

Indicators of Compromise

Unexpected child processes spawned by spoolsv.exe, particularly cmd.exe, powershell.exe, or rundll32.exe
New or modified files under C:\Windows\System32\spool\drivers\ or C:\Windows\System32\spool\PRINTERS\ outside of administrative driver installs
Creation of new printer ports or printer drivers by non-administrative accounts
Registry modifications under HKLM\SYSTEM\CurrentControlSet\Control\Print\ initiated by standard users

Detection Strategies

Enable Windows event logging for the Microsoft-Windows-PrintService/Admin and /Operational channels and forward to a centralized log platform
Alert on Event ID 808 (spooler failed to load a plug-in module) and Event ID 316 (printer driver installed) outside change windows
Hunt for process-creation events where spoolsv.exe is the parent of an interactive shell or scripting host
Correlate authentication events with spooler activity to identify low-privilege accounts triggering driver installs

Monitoring Recommendations

Baseline normal spooler RPC traffic and flag anomalous remote IRemoteWinspool or MS-RPRN calls from non-print-server hosts
Monitor for additions of new files into the spool\drivers subtree and validate against approved driver packages
Track creation of services, scheduled tasks, or registry Run keys originating from spoolsv.exe

How to Mitigate CVE-2022-23284

Immediate Actions Required

Apply the March 2022 Microsoft security updates that address CVE-2022-23284 to all affected Windows desktop and server builds
Inventory systems running the Print Spooler service and prioritize patching on domain controllers and multi-user servers
Restrict membership of groups that hold the high privileges required for exploitation
Audit installed printer drivers and remove unused or unsigned driver packages

Patch Information

Microsoft released fixes through the standard Windows Update channel on the March 2022 Patch Tuesday. Update KBs vary by operating system version and are enumerated in the Microsoft Security Update Advisory. Apply the cumulative update that matches each host's build number.

Workarounds

Disable the Print Spooler service (Stop-Service Spooler; Set-Service Spooler -StartupType Disabled) on systems that do not require printing, especially domain controllers
Enforce the RestrictDriverInstallationToAdministrators policy under HKLM\Software\Policies\Microsoft\Windows NT\Printers\PointAndPrint to block non-admin driver installs
Block inbound RPC to the spooler from untrusted network segments using host firewall rules

bash

# Disable Print Spooler on hosts that do not require printing
Stop-Service -Name Spooler -Force
Set-Service -Name Spooler -StartupType Disabled

# Enforce admin-only printer driver installation
New-ItemProperty -Path "HKLM:\Software\Policies\Microsoft\Windows NT\Printers\PointAndPrint" `
  -Name "RestrictDriverInstallationToAdministrators" -PropertyType DWORD -Value 1 -Force