CVE-2021-23874: McAfee Total Protection Privilege Escalation

CVE-2021-23874 Overview

CVE-2021-23874 is a Privilege Escalation and Arbitrary Code Execution vulnerability affecting McAfee Total Protection (MTP) prior to version 16.0.30. This vulnerability allows a local user to gain elevated privileges and execute arbitrary code by bypassing MTP's self-defense mechanisms. Due to improper privilege management and permission assignment flaws, an attacker with local access can leverage this vulnerability to completely compromise the affected system.

Critical Impact

This vulnerability is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, indicating active exploitation in the wild. Organizations using affected versions of McAfee Total Protection should prioritize remediation immediately.

Affected Products

• McAfee Total Protection versions prior to 16.0.30
• All platforms where McAfee Total Protection is deployed

Discovery Timeline

• 2021-02-10 - CVE-2021-23874 published to NVD
• 2025-11-03 - Last updated in NVD database

Technical Details for CVE-2021-23874

Vulnerability Analysis

This vulnerability stems from a combination of two critical weaknesses classified under CWE-269 (Improper Privilege Management) and CWE-732 (Incorrect Permission Assignment for Critical Resource). McAfee Total Protection implements self-defense mechanisms designed to prevent unauthorized processes from tampering with its components. However, a flaw in how these protections are enforced allows a local attacker to bypass these safeguards entirely.

The vulnerability requires local access to the target system but does not require user interaction to exploit. Once successfully exploited, an attacker gains the ability to execute arbitrary processes with elevated privileges, effectively bypassing the security controls that MTP is designed to provide.

Root Cause

The root cause of CVE-2021-23874 lies in improper privilege management (CWE-269) combined with incorrect permission assignment for critical resources (CWE-732). McAfee Total Protection's self-defense module fails to properly validate and restrict which processes can interact with protected components. This allows an attacker to craft a malicious process that circumvents the intended access controls, leading to privilege escalation.

The incorrect permission assignments allow local users to access and manipulate resources that should be restricted to system-level or administrative processes only. This architectural flaw undermines the fundamental security guarantees that the self-defense mechanism is intended to provide.

Attack Vector

The attack vector for CVE-2021-23874 is local, meaning an attacker must have prior access to the target system. The exploitation path involves:

1. A local user identifies the vulnerable MTP installation (versions prior to 16.0.30)
2. The attacker crafts a malicious process designed to bypass MTP self-defense mechanisms
3. Due to improper privilege management, the malicious process gains elevated privileges
4. The attacker achieves arbitrary code execution with elevated permissions

Since this vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, threat actors are actively leveraging this attack path in real-world scenarios. The low attack complexity and no user interaction requirement make this an attractive target for post-exploitation privilege escalation.

Detection Methods for CVE-2021-23874

Indicators of Compromise

• Unusual process execution originating from non-standard directories attempting to interact with McAfee Total Protection services
• Unexpected privilege escalation events associated with processes not typically requiring elevated permissions
• Modifications to McAfee Total Protection configuration files or registry entries by unauthorized processes
• Process injection attempts targeting McAfee self-defense components

Detection Strategies

• Monitor for processes attempting to bypass or disable McAfee Total Protection self-defense mechanisms
• Implement endpoint detection rules to identify privilege escalation attempts involving McAfee components
• Enable detailed process auditing to capture parent-child process relationships for suspicious activity
• Deploy behavioral analytics to detect anomalous interactions with security software components

Monitoring Recommendations

• Enable Windows Security Event logging for process creation events (Event ID 4688) with command line auditing
• Configure alerts for unexpected modifications to McAfee Total Protection service configurations
• Monitor for lateral movement attempts following potential exploitation of this vulnerability
• Implement continuous vulnerability scanning to identify systems running MTP versions prior to 16.0.30

How to Mitigate CVE-2021-23874

Immediate Actions Required

• Update McAfee Total Protection to version 16.0.30 or later immediately
• Audit all systems for vulnerable MTP installations and prioritize remediation based on exposure
• Implement application whitelisting to restrict unauthorized process execution pending patch deployment
• Isolate systems that cannot be immediately patched and increase monitoring for suspicious activity

Patch Information

McAfee has released a security update addressing this vulnerability in McAfee Total Protection version 16.0.30. Organizations should apply this update as soon as possible given the active exploitation status. Detailed patch information and installation guidance can be found in the McAfee FAQ Document TS103114. Due to the inclusion in the CISA Known Exploited Vulnerabilities catalog, federal agencies are mandated to remediate this vulnerability within specified timeframes.

Workarounds

• Restrict local user access to systems with vulnerable McAfee Total Protection installations
• Implement the principle of least privilege to limit the impact of potential exploitation
• Enable enhanced monitoring and logging on affected systems until patches can be applied
• Consider temporary deployment of additional endpoint protection layers to compensate for the self-defense bypass

# Verify McAfee Total Protection version
# Check installed version through Windows Programs and Features
# or via McAfee console to confirm version 16.0.30 or later is installed
# Update immediately if running a version prior to 16.0.30