CVE-2021-21069
📋 TL;DR
This vulnerability allows a local attacker to escalate privileges on systems running vulnerable versions of Adobe Creative Cloud Desktop Application. By exploiting insecure function calls in the installer, an attacker can perform high-privileged actions without user interaction. It affects users with Adobe Creative Cloud Desktop Application version 5.3 or earlier installed.
💻 Affected Systems
- Adobe Creative Cloud Desktop Application
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains full administrative control over the system, enabling installation of malware, data theft, or persistence mechanisms.
Likely Case
Local privilege escalation leading to unauthorized access to sensitive files or system settings.
If Mitigated
Limited impact if systems are patched or have strict user privilege controls, preventing local attackers from executing low-privileged code initially.
🎯 Exploit Status
Exploitation does not require user interaction, but an attacker must have local access to the system. No public proof-of-concept has been disclosed as of the advisory dates.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 5.4 or later
Vendor Advisory: https://helpx.adobe.com/security/products/creative-cloud/apsb21-18.html
Restart Required: Yes
Instructions:
1. Open Adobe Creative Cloud Desktop Application. 2. Go to Help > Check for Updates. 3. Install any available updates to version 5.4 or higher. 4. Restart the system if prompted.
🔧 Temporary Workarounds
Restrict Local User Privileges
allLimit standard user accounts to prevent execution of low-privileged code that could exploit this vulnerability.
🧯 If You Can't Patch
- Uninstall Adobe Creative Cloud Desktop Application if not essential.
- Implement strict access controls and monitor for suspicious local privilege escalation attempts.
🔍 How to Verify
Check if Vulnerable:
Check the installed version of Adobe Creative Cloud Desktop Application via the application's About menu or system settings.Check Version:
On Windows: Check in Control Panel > Programs > Programs and Features. On macOS: Use 'ls /Applications/Adobe\ Creative\ Cloud/ACC/*' or check via the app's About menu.Verify Fix Applied:
Confirm the version is 5.4 or later after updating.📡 Detection & Monitoring
Log Indicators:
- Unusual process creation by Adobe Creative Cloud installer, privilege escalation events in system logs.
Network Indicators:
- None, as this is a local vulnerability.
SIEM Query:
Example: Search for events where process name contains 'Creative Cloud' and privilege level changes, e.g., in Windows Event Logs (Event ID 4688).