CVE-2020-27907
📋 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 Catalina, Mojave, and Big Sur systems. Successful exploitation gives attackers complete control over the affected system.
💻 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
Complete system compromise with kernel-level persistence, data theft, and ability to bypass all security controls.
Likely Case
Local privilege escalation allowing malware to gain kernel privileges and establish persistence.
If Mitigated
Limited impact if systems are fully patched and have proper endpoint protection.
🎯 Exploit Status
Requires local access or ability to run malicious application. No public exploit code known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Big Sur 11.1, Security Update 2020-001 Catalina, Security Update 2020-007 Mojave, macOS Big Sur 11.0.1
Vendor Advisory: https://support.apple.com/en-us/HT211931
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update. 2. Install available security updates. 3. Restart when prompted.
🔧 Temporary Workarounds
Application Control
allRestrict execution of untrusted applications using MDM or endpoint security tools.
🧯 If You Can't Patch
- Implement strict application allowlisting to prevent execution of untrusted code.
- Use network segmentation to isolate vulnerable systems and limit lateral movement.
🔍 How to Verify
Check if Vulnerable:
Check macOS version: System Preferences > About This Mac. If version is older than patched versions listed, system is vulnerable.Check 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:
- Kernel panic logs
- Unexpected kernel extensions loading
- Processes running with root privileges from unusual locations
Network Indicators:
- Unusual outbound connections from kernel processes
SIEM Query:
Process creation events where parent process is kernel_task or processes gaining root privileges unexpectedly