CVE-2020-9824
📋 TL;DR
This macOS vulnerability allows non-privileged users to modify restricted network settings, potentially bypassing security controls. It affects macOS systems before Catalina 10.15.5. The issue could enable unauthorized network configuration changes.
💻 Affected Systems
- macOS
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker could reconfigure network settings to intercept traffic, bypass firewalls, redirect connections to malicious servers, or disable network security features entirely.
Likely Case
Local users could modify network proxy settings, DNS configurations, or VPN settings to bypass organizational security policies or enable man-in-the-middle attacks.
If Mitigated
With proper access controls and monitoring, impact is limited to local users who already have some system access, but they shouldn't be able to modify network settings.
🎯 Exploit Status
Exploitation requires local user access but no special privileges. The logic issue suggests relatively straightforward exploitation once understood.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Catalina 10.15.5
Vendor Advisory: https://support.apple.com/HT211170
Restart Required: Yes
Instructions:
1. Open System Preferences > Software Update
2. Install macOS Catalina 10.15.5 update
3. Restart the system when prompted
🔧 Temporary Workarounds
Restrict local user access
allLimit non-administrative user access to systems where network settings must remain secure
Monitor network configuration changes
allImplement monitoring for unexpected network setting modifications
🧯 If You Can't Patch
- Implement strict access controls to limit who can log into affected systems
- Monitor system logs for network configuration changes and investigate any unauthorized modifications
🔍 How to Verify
Check if Vulnerable:
Check macOS version: If version is earlier than 10.15.5, the system is vulnerableCheck Version:
sw_versVerify Fix Applied:
Verify macOS version is 10.15.5 or later via System Information or terminal command📡 Detection & Monitoring
Log Indicators:
- Unexpected network configuration changes in system logs
- Network preference modifications by non-admin users
Network Indicators:
- Sudden changes in network routing or proxy settings
- DNS configuration changes from affected systems
SIEM Query:
source="macos_system_logs" event_type="network_config_change" user!="admin"