CVE-2021-30942
📋 TL;DR
This memory corruption vulnerability in Apple's ColorSync ICC profile processing allows arbitrary code execution when processing malicious images. It affects macOS, iOS, iPadOS, tvOS, and watchOS users who open or process crafted image files. Attackers could gain full control of affected devices.
💻 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 →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
Complete system compromise with attacker gaining root privileges and persistent access to the device.
Likely Case
Malware installation, data theft, or ransomware deployment through malicious image files.
If Mitigated
Limited impact with proper network segmentation and application sandboxing in place.
🎯 Exploit Status
Public proof-of-concept exists on Packet Storm. Exploitation requires user interaction to process malicious image.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Big Sur 11.6.2, macOS Monterey 12.1, Security Update 2021-008 Catalina, 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. Open System Preferences > Software Update. 2. Install available updates. 3. Restart device when prompted.
🔧 Temporary Workarounds
Disable automatic image processing
allPrevent automatic processing of image files in applications
Use application sandboxing
allEnsure applications processing images run in sandboxed environments
🧯 If You Can't Patch
- Implement strict network filtering to block suspicious image downloads
- Use endpoint protection with memory corruption detection capabilities
🔍 How to Verify
Check if Vulnerable:
Check system version against affected versions list. On macOS: sw_vers -productVersionCheck Version:
macOS: sw_vers -productVersion, iOS/iPadOS: Settings > General > About > VersionVerify Fix Applied:
Verify system version is equal to or newer than patched versions listed in fix_official section📡 Detection & Monitoring
Log Indicators:
- Unexpected crashes in image processing applications
- Memory access violations in system logs
Network Indicators:
- Unusual image file downloads from untrusted sources
- Suspicious file transfers to endpoints
SIEM Query:
source="*system.log*" AND ("ColorSync" OR "ICC" OR "image processing") AND ("crash" OR "segfault" OR "memory")🔗 References
- http://packetstormsecurity.com/files/165559/Apple-ColorSync-Out-Of-Bounds-Read.html
- 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/HT212979
- https://support.apple.com/en-us/HT212980
- https://support.apple.com/en-us/HT212981
- http://packetstormsecurity.com/files/165559/Apple-ColorSync-Out-Of-Bounds-Read.html
- 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/HT212979
- https://support.apple.com/en-us/HT212980
- https://support.apple.com/en-us/HT212981
