CVE-2021-31002
📋 TL;DR
This vulnerability allows a malicious application to execute arbitrary code with system privileges on affected macOS systems. It's an out-of-bounds read issue that was fixed in macOS updates. All users running vulnerable macOS versions are affected.
💻 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 →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
Full system compromise with attacker gaining root/system privileges, allowing installation of persistent malware, data theft, and complete control of the system.
Likely Case
Malicious application exploiting the vulnerability to gain elevated privileges, potentially leading to data exfiltration, ransomware deployment, or backdoor installation.
If Mitigated
Limited impact with proper application sandboxing and security controls, though successful exploitation would still grant system privileges.
🎯 Exploit Status
Exploitation requires user to run a malicious application. No public exploit code is known, but Apple has confirmed the vulnerability could lead to arbitrary code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Monterey 12.0.1, macOS Big Sur 11.6.2
Vendor Advisory: https://support.apple.com/en-us/HT212869
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update. 2. Install available updates for macOS. 3. Restart the system when prompted.
🔧 Temporary Workarounds
Application Restriction
macosRestrict installation and execution of untrusted applications
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 suspicious privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check macOS version: if running macOS Big Sur earlier than 11.6.2 or macOS Monterey earlier than 12.0.1, system is vulnerable.Check Version:
sw_versVerify Fix Applied:
Verify macOS version is 12.0.1 or later for Monterey, or 11.6.2 or later for Big Sur.📡 Detection & Monitoring
Log Indicators:
- Unexpected privilege escalation events
- Suspicious application launches with elevated privileges
- Kernel extension loading anomalies
Network Indicators:
- Unusual outbound connections from system processes
- Command and control traffic from privileged processes
SIEM Query:
process where parent_process_name contains "launchd" and process_name not in (approved_list) and integrity_level changes