CVE-2020-27916
📋 TL;DR
CVE-2020-27916 is an out-of-bounds write vulnerability in Apple's audio file processing that could allow arbitrary code execution when processing malicious audio files. It affects macOS, iOS, iPadOS, tvOS, and watchOS users running vulnerable versions. Attackers could exploit this to gain 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 →Tvos by Apple
Watchos by Apple
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining root privileges and persistent access to the device.
Likely Case
Local privilege escalation or remote code execution if user opens a malicious audio file.
If Mitigated
Limited impact with proper patch management and user awareness about opening untrusted files.
🎯 Exploit Status
Exploitation requires user interaction to open malicious audio file. Proof-of-concept details available in public disclosures.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Big Sur 11.0.1, iOS 14.2, iPadOS 14.2, tvOS 14.2, watchOS 7.1
Vendor Advisory: https://support.apple.com/en-us/HT211928
Restart Required: Yes
Instructions:
1. Go to System Preferences > Software Update (macOS) or Settings > General > Software Update (iOS/iPadOS). 2. Install available updates. 3. Restart device when prompted.
🔧 Temporary Workarounds
Disable automatic audio file processing
allPrevent automatic processing of audio files in web browsers and email clients
User education
allTrain users not to open audio files from untrusted sources
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of unauthorized audio processing applications
- Use network filtering to block download of audio files from untrusted sources
🔍 How to Verify
Check if Vulnerable:
Check system version against affected versions. On macOS: System Information > Software > System Version. On iOS: Settings > General > About > Version.Check Version:
macOS: sw_vers -productVersion, iOS: Settings > General > About > VersionVerify Fix Applied:
Verify system version is at or above: macOS 11.0.1, iOS 14.2, iPadOS 14.2, tvOS 14.2, watchOS 7.1📡 Detection & Monitoring
Log Indicators:
- Unexpected crashes in audio processing services
- Suspicious file downloads with audio extensions
Network Indicators:
- Downloads of audio files from suspicious sources
- Unusual outbound connections after audio file processing
SIEM Query:
source="*audio*" AND (event="crash" OR event="exception") OR file_extension IN ("mp3", "wav", "aac", "m4a") AND download_source="suspicious"🔗 References
- http://seclists.org/fulldisclosure/2020/Dec/26
- http://seclists.org/fulldisclosure/2020/Dec/32
- https://support.apple.com/en-us/HT211928
- https://support.apple.com/en-us/HT211929
- https://support.apple.com/en-us/HT211930
- https://support.apple.com/en-us/HT211931
- https://support.apple.com/kb/HT212011
- http://seclists.org/fulldisclosure/2020/Dec/26
- http://seclists.org/fulldisclosure/2020/Dec/32
- https://support.apple.com/en-us/HT211928
- https://support.apple.com/en-us/HT211929
- https://support.apple.com/en-us/HT211930
- https://support.apple.com/en-us/HT211931
- https://support.apple.com/kb/HT212011
