CVE-2023-27938
📋 TL;DR
This vulnerability in GarageBand for macOS allows attackers to execute arbitrary code or cause application crashes by tricking users into opening malicious MIDI files. It affects macOS users running GarageBand versions before 10.4.8. The out-of-bounds read issue can be exploited without user interaction beyond file opening.
💻 Affected Systems
- GarageBand
📦 What is this software?
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 →⚠️ Risk & Real-World Impact
Worst Case
Full system compromise through arbitrary code execution with user privileges, potentially leading to data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Application crashes (denial of service) when users open malicious MIDI files, with occasional successful code execution leading to limited privilege escalation.
If Mitigated
No impact if GarageBand is not installed, if the patch is applied, or if users avoid opening untrusted MIDI files.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file). No public exploit code has been reported as of analysis date.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 10.4.8
Vendor Advisory: https://support.apple.com/en-us/HT213650
Restart Required: Yes
Instructions:
1. Open App Store on macOS. 2. Click 'Updates' in sidebar. 3. Find GarageBand update. 4. Click 'Update' button. 5. Restart computer after installation completes.
🔧 Temporary Workarounds
Disable GarageBand file associations
allPrevent MIDI files from automatically opening in GarageBand
Right-click any .mid or .midi file > Get Info > Open With > Choose different application > Change All
Restrict GarageBand execution
allUse macOS parental controls or MDM to restrict GarageBand usage
System Preferences > Screen Time > Content & Privacy > App Limits
🧯 If You Can't Patch
- Uninstall GarageBand if not needed
- Implement application whitelisting to block GarageBand execution
🔍 How to Verify
Check if Vulnerable:
Open GarageBand > GarageBand menu > About GarageBand, check if version is earlier than 10.4.8Check Version:
defaults read /Applications/GarageBand.app/Contents/Info.plist CFBundleShortVersionStringVerify Fix Applied:
Confirm GarageBand version is 10.4.8 or later in About GarageBand dialog📡 Detection & Monitoring
Log Indicators:
- GarageBand crash logs in ~/Library/Logs/DiagnosticReports
- Unexpected GarageBand process launches
Network Indicators:
- Unusual outbound connections from GarageBand process
SIEM Query:
process_name:"GarageBand" AND (event_type:"crash" OR parent_process:"launchd")