CVE-2021-43755
📋 TL;DR
This CVE describes an out-of-bounds write vulnerability in Adobe After Effects that could allow arbitrary code execution when a user opens a malicious file. Attackers could gain the same privileges as the current user. Users of Adobe After Effects versions 22.0 and earlier, and 18.4.2 and earlier are affected.
💻 Affected Systems
- Adobe After Effects
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full 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 data exfiltration or malware installation on the affected system.
If Mitigated
Limited impact with proper user awareness training and file validation controls in place.
🎯 Exploit Status
Requires user to open a specially crafted malicious file. No public exploit code available at time of advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: After Effects 22.1 and 18.4.3
Vendor Advisory: https://helpx.adobe.com/security/products/after_effects/apsb21-115.html
Restart Required: Yes
Instructions:
1. Open Adobe Creative Cloud application. 2. Navigate to 'Apps' section. 3. Find Adobe After Effects. 4. Click 'Update' button. 5. Wait for download and installation to complete. 6. Restart computer if prompted.
🔧 Temporary Workarounds
Restrict file opening
allConfigure system policies to prevent opening untrusted After Effects files
User awareness training
allTrain users to only open After Effects files from trusted sources
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of malicious code
- Use endpoint detection and response (EDR) solutions to monitor for suspicious After Effects behavior
🔍 How to Verify
Check if Vulnerable:
Check After Effects version via Help > About After Effects menuCheck Version:
On Windows: Check via Creative Cloud app or Help > About menu. On macOS: Check via Creative Cloud app or After Effects > About After Effects menu.Verify Fix Applied:
Verify version is 22.1 or higher, or 18.4.3 or higher📡 Detection & Monitoring
Log Indicators:
- Unexpected After Effects crashes
- Suspicious file opening events in application logs
Network Indicators:
- Unusual outbound connections from After Effects process
SIEM Query:
process_name:"AfterFX.exe" AND (event_type:crash OR file_path:contains:".aep" AND source_ip:external)