CVE-2021-1882
📋 TL;DR
CVE-2021-1882 is a critical memory corruption vulnerability in Apple operating systems that allows an application to gain elevated privileges. This affects iOS, iPadOS, macOS, watchOS, and tvOS systems. Attackers could potentially execute arbitrary code with kernel-level privileges.
💻 Affected Systems
- iOS
- iPadOS
- macOS
- watchOS
- tvOS
📦 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
Full system compromise with kernel-level code execution, allowing complete control over the device, data theft, and persistence.
Likely Case
Malicious applications bypassing sandbox restrictions to access sensitive data or perform unauthorized actions.
If Mitigated
Limited impact with proper application vetting and security controls, though kernel access remains dangerous.
🎯 Exploit Status
Exploitation requires user to run a malicious application, but no authentication is needed once the app is executed. Memory corruption vulnerabilities in Apple's kernel are frequently targeted.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: iOS 14.5, iPadOS 14.5, macOS Big Sur 11.3, Security Update 2021-002 Catalina, watchOS 7.4, tvOS 14.5
Vendor Advisory: https://support.apple.com/en-us/HT212317
Restart Required: Yes
Instructions:
1. Open Settings app. 2. Go to General > Software Update. 3. Install the latest available update. 4. Restart device when prompted.
🔧 Temporary Workarounds
Application Restriction
allRestrict installation of applications from untrusted sources to prevent malicious apps from being installed.
🧯 If You Can't Patch
- Implement strict application allowlisting to prevent unauthorized apps from executing.
- Isolate vulnerable devices from critical networks and monitor for suspicious application behavior.
🔍 How to Verify
Check if Vulnerable:
Check current OS version against affected versions list. On iOS/iPadOS: Settings > General > About > Version. On macOS: Apple menu > About This Mac.Check Version:
iOS/iPadOS: Settings > General > About > Version. macOS: sw_vers or System Information app.Verify Fix Applied:
Verify OS version is equal to or newer than the patched versions listed in the fix section.📡 Detection & Monitoring
Log Indicators:
- Unexpected kernel panics
- Application privilege escalation attempts
- Unusual process spawning with elevated privileges
Network Indicators:
- Unusual outbound connections from system processes
- Command and control traffic from unexpected sources
SIEM Query:
Process creation events where parent process is a user application and child process has SYSTEM/root privileges on Apple devices.🔗 References
- https://support.apple.com/en-us/HT212317
- https://support.apple.com/en-us/HT212323
- https://support.apple.com/en-us/HT212324
- https://support.apple.com/en-us/HT212325
- https://support.apple.com/en-us/HT212326
- https://support.apple.com/en-us/HT212317
- https://support.apple.com/en-us/HT212323
- https://support.apple.com/en-us/HT212324
- https://support.apple.com/en-us/HT212325
- https://support.apple.com/en-us/HT212326
