CVE-2021-30672
📋 TL;DR
This memory corruption vulnerability in macOS allows malicious applications to gain root privileges through improper state management. It affects macOS Big Sur, Catalina, and Mojave systems. Attackers could execute arbitrary code with highest system privileges.
💻 Affected Systems
- macOS
📦 What is this software?
Macos by Apple
macOS is Apple's desktop and laptop operating system powering Mac computers used by millions of professionals, developers, creative professionals, and enterprise users worldwide. Built on a Unix foundation with the Darwin kernel and modern Cocoa frameworks, macOS delivers a seamless ecosystem integr...
Learn more about Macos →⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with root-level persistence, data exfiltration, and lateral movement across the network.
Likely Case
Local privilege escalation allowing malicious applications to bypass security controls and install persistent malware.
If Mitigated
Limited impact if systems are fully patched and application execution is restricted through security policies.
🎯 Exploit Status
Requires user to execute malicious application. Memory corruption vulnerabilities typically require specific conditions to trigger reliably.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Big Sur 11.4, Security Update 2021-004 Catalina, Security Update 2021-005 Mojave
Vendor Advisory: https://support.apple.com/en-us/HT212529
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update. 2. Install available security updates. 3. Restart system when prompted. 4. Verify update completion in About This Mac.
🔧 Temporary Workarounds
Application Restriction
allRestrict execution of untrusted applications using Gatekeeper and application whitelisting
sudo spctl --master-enable
sudo spctl --enable --label "Developer ID"
🧯 If You Can't Patch
- Implement strict application control policies to prevent execution of untrusted applications
- Use endpoint detection and response (EDR) solutions to monitor for privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check macOS version in About This Mac. If version is Big Sur < 11.4, Catalina without 2021-004, or Mojave without 2021-005, system is vulnerable.Check Version:
sw_versVerify Fix Applied:
Verify macOS version shows Big Sur 11.4 or later, or Catalina/Mojave with appropriate security updates installed.📡 Detection & Monitoring
Log Indicators:
- Unexpected privilege escalation events in system.log
- Process creation with elevated privileges from untrusted sources
Network Indicators:
- Unusual outbound connections following local privilege escalation
SIEM Query:
source="macos_system.log" AND (event="privilege_escalation" OR process_elevation=true)