CVE-2020-27909
📋 TL;DR
CVE-2020-27909 is an out-of-bounds read vulnerability in Apple's audio file processing that could allow arbitrary code execution when processing a malicious audio file. This affects iOS, iPadOS, tvOS, and watchOS users who process untrusted audio files. Successful exploitation could give attackers control over affected devices.
💻 Affected Systems
- 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 device compromise with attacker gaining root privileges and persistent access to sensitive data, communications, and device functions.
Likely Case
Application crash or limited data leakage from memory, though arbitrary code execution is possible with crafted exploits.
If Mitigated
No impact if devices are patched to iOS 14.2/iPadOS 14.2/tvOS 14.2/watchOS 7.1 or later, or if untrusted audio files are blocked.
🎯 Exploit Status
Exploitation requires user to open/process a malicious audio file; no known public exploits but Apple's disclosure suggests active concern.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 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 Settings > General > Software Update. 2. Download and install iOS 14.2/iPadOS 14.2/tvOS 14.2/watchOS 7.1 or later. 3. Restart device after installation completes.
🔧 Temporary Workarounds
Block untrusted audio files
allPrevent processing of audio files from untrusted sources via email, messaging apps, or websites.
Disable automatic media processing
allConfigure apps to not automatically process or preview audio files from unknown sources.
🧯 If You Can't Patch
- Isolate affected devices from critical networks and data
- Implement application whitelisting to block untrusted audio processing apps
🔍 How to Verify
Check if Vulnerable:
Check device version in Settings > General > About > Software Version. If version is earlier than iOS 14.2, iPadOS 14.2, tvOS 14.2, or watchOS 7.1, device is vulnerable.Check Version:
Not applicable - check via device settings interfaceVerify Fix Applied:
Confirm device shows iOS 14.2, iPadOS 14.2, tvOS 14.2, or watchOS 7.1 or later in Settings > General > About > Software Version.📡 Detection & Monitoring
Log Indicators:
- Application crashes in media processing apps
- Unexpected audio file processing from untrusted sources
Network Indicators:
- Downloads of unusual audio file types from suspicious sources
SIEM Query:
Not typically applicable for mobile device vulnerabilities; monitor for patch compliance via MDM systems🔗 References
- 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/kb/HT211931
- https://www.zerodayinitiative.com/advisories/ZDI-21-374/
- 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/kb/HT211931
- https://www.zerodayinitiative.com/advisories/ZDI-21-374/
