CVE-2020-27947
📋 TL;DR
This is a memory corruption vulnerability in macOS kernel that allows an application to execute arbitrary code with kernel privileges. It affects macOS Mojave, Catalina, and Big Sur versions before specific security updates. Attackers could gain complete system control.
💻 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 kernel-level persistence, data theft, and backdoor installation
Likely Case
Local privilege escalation allowing attackers to bypass security controls and access sensitive data
If Mitigated
Limited impact if systems are patched and proper application sandboxing is enforced
🎯 Exploit Status
Requires local access and ability to execute code; kernel exploitation typically requires specific expertise
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Big Sur 11.1, Security Update 2020-001 Catalina, Security Update 2020-007 Mojave
Vendor Advisory: https://support.apple.com/en-us/HT212011
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update. 2. Install available security updates. 3. Restart when prompted.
🔧 Temporary Workarounds
Application Whitelisting
macOSRestrict execution of untrusted applications using macOS security features
🧯 If You Can't Patch
- Implement strict application control policies to prevent execution of untrusted code
- Segment network to limit lateral movement from potentially compromised macOS systems
🔍 How to Verify
Check if Vulnerable:
Check macOS version: if running Mojave, Catalina, or Big Sur without the specified security updates, system is vulnerableCheck Version:
sw_versVerify Fix Applied:
Verify macOS version matches patched versions: Big Sur 11.1+, Catalina with Security Update 2020-001, Mojave with Security Update 2020-007📡 Detection & Monitoring
Log Indicators:
- Unusual kernel extensions loading
- Suspicious privilege escalation attempts in system logs
Network Indicators:
- Unexpected outbound connections from kernel processes
SIEM Query:
source="macos_system_logs" AND (event="kernel_extension_load" OR event="privilege_escalation")