CVE-2021-30993
📋 TL;DR
A buffer overflow vulnerability in Apple operating systems allows attackers in privileged network positions to execute arbitrary code. This affects macOS, iOS, iPadOS, tvOS, and watchOS before specific security updates. The vulnerability could lead to complete system compromise.
💻 Affected Systems
- macOS
- iOS
- iPadOS
- tvOS
- watchOS
📦 What is this software?
Ipados by Apple
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 →Tvos by Apple
Watchos by Apple
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full system compromise, data theft, and persistent access
Likely Case
Privileged network attacker gains code execution on vulnerable devices
If Mitigated
Limited impact with proper network segmentation and updated systems
🎯 Exploit Status
Requires attacker to be in a privileged network position. No public exploit code available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Monterey 12.1, iOS 15.2, iPadOS 15.2, tvOS 15.2, watchOS 8.3
Vendor Advisory: https://support.apple.com/en-us/HT212975
Restart Required: Yes
Instructions:
1. Go to Settings > General > Software Update on iOS/iPadOS/watchOS/tvOS. 2. Install available updates. 3. For macOS, go to System Preferences > Software Update. 4. Install macOS Monterey 12.1 or later. 5. Restart device after installation.
🔧 Temporary Workarounds
Network Segmentation
allIsolate vulnerable devices from untrusted networks and limit network access
Disable Unnecessary Services
allReduce attack surface by disabling unused network services
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable devices
- Monitor network traffic for unusual patterns and implement network-based intrusion detection
🔍 How to Verify
Check if Vulnerable:
Check current OS version against affected versions listCheck Version:
iOS/iPadOS: Settings > General > About > Version. macOS: Apple menu > About This Mac > macOS version. tvOS: Settings > General > About > Version. watchOS: iPhone Watch app > General > About > Version.Verify Fix Applied:
Verify OS version is equal to or newer than patched versions📡 Detection & Monitoring
Log Indicators:
- Unusual process creation
- Memory access violations
- Network service crashes
Network Indicators:
- Unusual network traffic to/from Apple devices
- Suspicious network connections to privileged ports
SIEM Query:
source="apple-devices" AND (event_type="process_creation" OR event_type="crash") AND severity=HIGH🔗 References
- https://support.apple.com/en-us/HT212975
- https://support.apple.com/en-us/HT212976
- https://support.apple.com/en-us/HT212978
- https://support.apple.com/en-us/HT212980
- https://support.apple.com/en-us/HT212975
- https://support.apple.com/en-us/HT212976
- https://support.apple.com/en-us/HT212978
- https://support.apple.com/en-us/HT212980
