CVE-2020-9990
📋 TL;DR
This macOS kernel vulnerability allows a malicious application to exploit a race condition to execute arbitrary code with kernel privileges. It affects macOS systems before Catalina 10.15.6. Attackers could gain complete control of affected systems.
💻 Affected Systems
- macOS
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with kernel-level persistence, data theft, and backdoor installation.
Likely Case
Malicious application escalates privileges to install malware, keyloggers, or ransomware.
If Mitigated
Limited impact if systems are patched and application execution is restricted.
🎯 Exploit Status
Race condition exploitation requires precise timing and local code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Catalina 10.15.6
Vendor Advisory: https://support.apple.com/kb/HT211289
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update
2. Install macOS Catalina 10.15.6 update
3. Restart when prompted
🔧 Temporary Workarounds
Restrict application execution
macOSUse macOS Gatekeeper and application whitelisting to prevent unauthorized applications from running.
sudo spctl --master-enable
sudo spctl --enable --label "Developer ID"
🧯 If You Can't Patch
- Implement strict application control policies to prevent unauthorized software execution
- Monitor for suspicious process creation and privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check macOS version: if below 10.15.6, system is vulnerable.Check Version:
sw_versVerify Fix Applied:
Verify macOS version is 10.15.6 or later.📡 Detection & Monitoring
Log Indicators:
- Unexpected kernel extensions loading
- Process privilege escalation from user to root
Network Indicators:
- None - local exploitation only
SIEM Query:
process where parent_process_name contains "kernel" and process_name not in approved_list