CVE-2021-21102
📋 TL;DR
CVE-2021-21102 is a path traversal vulnerability in Adobe Illustrator that allows arbitrary code execution when a malicious file is opened. Attackers can exploit this to run code with the victim's user privileges. All users running Adobe Illustrator version 25.2 or earlier are affected.
💻 Affected Systems
- Adobe Illustrator
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control of the victim's machine and potentially moving laterally within the network.
Likely Case
Local privilege escalation leading to data theft, ransomware deployment, or persistent backdoor installation on the affected system.
If Mitigated
Limited impact if file execution is blocked or sandboxed, though some data exposure may still occur.
🎯 Exploit Status
Exploitation requires user to open malicious file. No authentication bypass needed beyond tricking user.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 25.2.1 or later
Vendor Advisory: https://helpx.adobe.com/security/products/illustrator/apsb21-24.html
Restart Required: Yes
Instructions:
1. Open Adobe Creative Cloud application. 2. Navigate to 'Apps' tab. 3. Find Adobe Illustrator and click 'Update'. 4. Restart Illustrator after update completes.
🔧 Temporary Workarounds
Block Illustrator file execution
allUse application control to block execution of .ai files from untrusted sources
Disable Illustrator file associations
windowsRemove .ai file association with Illustrator to prevent automatic opening
🧯 If You Can't Patch
- Implement strict email filtering to block malicious attachments
- Educate users to never open Illustrator files from untrusted sources
🔍 How to Verify
Check if Vulnerable:
Check Illustrator version via Help > About Illustrator. If version is 25.2 or earlier, system is vulnerable.Check Version:
On Windows: Check registry at HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\Illustrator\25.0\AMT\VersionVerify Fix Applied:
Verify version is 25.2.1 or later in Help > About Illustrator.📡 Detection & Monitoring
Log Indicators:
- Unusual Illustrator process spawning child processes
- Illustrator accessing unexpected file paths
Network Indicators:
- Illustrator process making unexpected network connections after file open
SIEM Query:
process_name:"Illustrator.exe" AND (process_spawn:* OR file_access:*..\*)