CVE-2022-2313: McAfee Agent Privilege Escalation Flaw

CVE-2022-2313 Overview

A DLL hijacking vulnerability exists in the MA Smart Installer for Windows prior to version 5.7.7. This security flaw allows local users to execute arbitrary code and obtain elevated privileges by strategically placing a malicious DLL into the folder from which the Smart Installer is executed. The vulnerability exploits the insecure DLL loading behavior of the installer, enabling attackers to gain higher privileges on affected systems.

Critical Impact

Local privilege escalation through DLL hijacking allows attackers to execute arbitrary code with elevated privileges, potentially compromising the entire system's security posture.

Affected Products

• McAfee Agent for Windows (versions prior to 5.7.7)
• MA Smart Installer for Windows

Discovery Timeline

• 2022-07-27 - CVE-2022-2313 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-2313

Vulnerability Analysis

This vulnerability falls under CWE-427 (Uncontrolled Search Path Element), a class of weaknesses where an application searches for critical resources in locations that could be under attacker control. The MA Smart Installer fails to properly validate the DLL loading path, allowing an attacker to introduce a malicious DLL that will be loaded and executed with the installer's privileges.

When the Smart Installer is launched from a directory where the user has write access, an attacker can place a specially crafted DLL file in that location. The installer will load this malicious DLL during its execution sequence, resulting in arbitrary code execution with the privileges of the installer process. This local attack vector requires an attacker to have some level of access to the system and user interaction to trigger the installer execution from the compromised directory.

Root Cause

The root cause of this vulnerability is improper DLL search order implementation in the MA Smart Installer. Windows applications typically follow a specific search order when loading DLLs, and when this process is not properly secured, it creates an opportunity for DLL hijacking attacks. The Smart Installer does not adequately restrict the search path or validate the integrity of loaded DLLs, allowing malicious libraries to be loaded from the current working directory or other attacker-controlled locations.

Attack Vector

The attack requires local access to the target system and involves the following sequence:

1. An attacker identifies a writable directory where the Smart Installer may be executed
2. A malicious DLL with a name matching one of the expected system DLLs is crafted
3. The malicious DLL is placed in the target directory
4. When a user executes the Smart Installer from that directory, the malicious DLL is loaded
5. The attacker's code executes with the privileges of the installer process

The vulnerability requires user interaction (launching the installer from the compromised location) and low privileges for initial access, but can result in high impact to confidentiality, integrity, and availability of the system.

Detection Methods for CVE-2022-2313

Indicators of Compromise

• Unexpected DLL files appearing in directories where the MA Smart Installer is located
• Unusual process behavior or child processes spawned by the Smart Installer
• Presence of suspicious DLL files with names commonly targeted in DLL hijacking attacks
• Anomalous file creation or modification events in installer directories

Detection Strategies

• Monitor for DLL loading events from non-standard or user-writable directories during Smart Installer execution
• Implement application whitelisting to prevent unauthorized DLL loading
• Deploy endpoint detection tools to identify suspicious DLL placement patterns
• Audit file system changes in directories commonly used for software installation

Monitoring Recommendations

• Enable Windows Event Logging for process creation and DLL loading events
• Configure security tools to alert on unsigned or unexpected DLLs loaded by McAfee Agent installers
• Monitor for privilege escalation attempts following installer execution
• Implement file integrity monitoring on directories containing installation files

How to Mitigate CVE-2022-2313

Immediate Actions Required

• Upgrade McAfee Agent to version 5.7.7 or later immediately
• Review and audit all systems running vulnerable versions of the MA Smart Installer
• Ensure installers are only executed from trusted, write-protected directories
• Implement the principle of least privilege for user accounts

Patch Information

McAfee (now Trellix) has released a security update addressing this vulnerability. Upgrade to McAfee Agent version 5.7.7 or later to remediate this issue. For detailed patching instructions and additional information, refer to the Trellix Security Advisory SB10385.

Workarounds

• Execute the Smart Installer only from protected system directories where standard users do not have write access
• Remove write permissions from directories containing installation files
• Implement application control policies to prevent execution of unauthorized DLLs
• Use administrative-only directories for installer execution until patching is complete

# Example: Restrict write permissions on installer directory
icacls "C:\McAfeeInstaller" /inheritance:r
icacls "C:\McAfeeInstaller" /grant:r "SYSTEM:(OI)(CI)F"
icacls "C:\McAfeeInstaller" /grant:r "Administrators:(OI)(CI)F"
icacls "C:\McAfeeInstaller" /grant:r "Users:(OI)(CI)RX"