CVE-2020-29633
📋 TL;DR
This macOS authentication bypass vulnerability allows attackers in a privileged network position to circumvent authentication policies. It affects multiple macOS versions including Big Sur, Catalina, and Mojave. Successful exploitation could lead to unauthorized access to protected resources.
💻 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 administrative privileges, data exfiltration, and persistent backdoor installation.
Likely Case
Unauthorized access to sensitive data and services, privilege escalation within the network.
If Mitigated
Limited impact with proper network segmentation and monitoring, though authentication bypass remains possible.
🎯 Exploit Status
Requires network access and understanding of macOS authentication mechanisms. No public exploit code available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 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 system when prompted.
🔧 Temporary Workarounds
Network Segmentation
allLimit network access to vulnerable systems to trusted networks only
Enhanced Monitoring
allMonitor authentication logs for unusual patterns or bypass attempts
🧯 If You Can't Patch
- Implement strict network access controls and segmentation
- Enable detailed authentication logging and monitoring for suspicious activity
🔍 How to Verify
Check if Vulnerable:
Check macOS version via 'sw_vers' command and compare with affected versionsCheck Version:
sw_versVerify Fix Applied:
Verify macOS version is 11.2 or higher for Big Sur, or has appropriate security updates for Catalina/Mojave📡 Detection & Monitoring
Log Indicators:
- Failed authentication attempts followed by successful access
- Authentication policy bypass events
Network Indicators:
- Unusual authentication traffic patterns
- Network traffic from unexpected sources to authentication endpoints
SIEM Query:
source="macOS" AND (event_type="authentication" AND result="success" AND previous_result="failure")