CVE-2020-27914
📋 TL;DR
This memory corruption vulnerability in macOS allows malicious applications to execute arbitrary code with system privileges. It affects macOS Catalina, Mojave, and Big Sur systems. Attackers could gain complete control of affected systems.
💻 Affected Systems
- macOS
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining root privileges, enabling installation of persistent malware, data theft, and complete system control.
Likely Case
Malicious application exploiting the vulnerability to gain elevated privileges, potentially leading to data exfiltration or ransomware deployment.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions in place.
🎯 Exploit Status
Requires user to execute malicious application. No public exploit code available at disclosure.
🛠️ 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/HT211931
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update. 2. Install available security updates. 3. Restart system when prompted.
🔧 Temporary Workarounds
Application Restriction
allRestrict installation and execution of untrusted applications
sudo spctl --master-enable
sudo spctl --enable --label "Developer ID"
🧯 If You Can't Patch
- Implement strict application allowlisting to prevent execution of untrusted applications
- Use standard user accounts instead of admin accounts for daily use
🔍 How to Verify
Check if Vulnerable:
Check macOS version: sw_vers -productVersionCheck Version:
sw_vers -productVersionVerify Fix Applied:
Verify macOS version is 11.1 or higher for Big Sur, or has security updates 2020-001/2020-007 installed📡 Detection & Monitoring
Log Indicators:
- Unexpected privilege escalation events
- Suspicious application execution with elevated privileges
Network Indicators:
- Unusual outbound connections from system processes
SIEM Query:
process where parent_process_name contains "launchd" and process_name not in (approved_list) and integrity_level changed