CVE-2021-40754
📋 TL;DR
This vulnerability allows attackers to execute arbitrary code on systems running vulnerable versions of Adobe After Effects. Attackers can achieve this by tricking users into opening malicious WAV files. Users of Adobe After Effects versions 18.4.1 and earlier are affected.
💻 Affected Systems
- Adobe After Effects
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining the same privileges as the current user, potentially leading to data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Local privilege escalation leading to unauthorized access to sensitive files, system configuration changes, or installation of additional malware.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially resulting only in application crash or denial of service.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file). No public exploit code available at disclosure time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 18.4.2 or later
Vendor Advisory: https://helpx.adobe.com/security/products/after_effects/apsb21-79.html
Restart Required: Yes
Instructions:
1. Open Adobe Creative Cloud application
2. Navigate to 'Apps' section
3. Find Adobe After Effects in your installed applications
4. Click 'Update' button if available
5. Alternatively, download latest version from Adobe website
6. Install update and restart system
🔧 Temporary Workarounds
File Type Restriction
allBlock WAV files from untrusted sources using application control or file filtering
User Awareness
allTrain users to only open WAV files from trusted sources and verify file integrity
🧯 If You Can't Patch
- Run Adobe After Effects with minimal user privileges (non-admin account)
- Implement application whitelisting to prevent execution of unauthorized code
🔍 How to Verify
Check if Vulnerable:
Check Adobe After Effects version in Help > About After Effects menuCheck Version:
On Windows: Check registry at HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\After Effects\XX.X\InstallPath. On macOS: Check /Applications/Adobe After Effects XX.X/Adobe After Effects.app/Contents/Info.plistVerify Fix Applied:
Verify version is 18.4.2 or later in Help > About After Effects menu📡 Detection & Monitoring
Log Indicators:
- Application crashes with WAV file processing
- Unexpected child processes spawned from After Effects
- File access to suspicious WAV files
Network Indicators:
- Outbound connections from After Effects process to unknown IPs
- DNS queries for suspicious domains after file opening
SIEM Query:
process_name:"AfterFX.exe" AND (event_type:process_creation OR event_type:crash)