CVE-2019-16470
📋 TL;DR
A stack-based buffer overflow vulnerability in Adobe Acrobat Reader allows attackers to execute arbitrary code when a user opens a malicious PDF file. This affects users running vulnerable versions of Adobe Acrobat Reader DC and Acrobat Reader DC Classic on Windows and macOS systems. Successful exploitation requires user interaction but could lead to complete system compromise.
💻 Affected Systems
- Adobe Acrobat Reader DC
- Adobe Acrobat Reader DC Classic
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining the same privileges as the logged-in user, potentially leading to data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Malicious PDF files delivered via phishing emails or malicious websites lead to system compromise when opened by users, resulting in credential theft or malware installation.
If Mitigated
With proper patching and security controls, the risk is limited to isolated incidents that can be contained through endpoint detection and user awareness.
🎯 Exploit Status
Exploitation requires user interaction to open malicious PDF. Multiple proof-of-concepts exist in public repositories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2019.021.20061 and later
Vendor Advisory: https://helpx.adobe.com/security/products/acrobat/apsb19-55.html
Restart Required: Yes
Instructions:
1. Open Adobe Acrobat Reader DC. 2. Go to Help > Check for Updates. 3. Follow prompts to install update. 4. Restart computer if required. 5. Verify version is 2019.021.20061 or later.
🔧 Temporary Workarounds
Disable JavaScript in Adobe Reader
allDisabling JavaScript prevents many PDF-based exploits from executing
Edit > Preferences > JavaScript > Uncheck 'Enable Acrobat JavaScript'
Use Protected View
allEnable Protected View for files from potentially unsafe locations
Edit > Preferences > Security (Enhanced) > Enable Protected View at startup
🧯 If You Can't Patch
- Implement application whitelisting to block unauthorized PDF readers
- Deploy email filtering to block malicious PDF attachments and train users to avoid opening suspicious files
🔍 How to Verify
Check if Vulnerable:
Check Adobe Reader version: Open Adobe Reader, go to Help > About Adobe Acrobat Reader DC. If version is 2019.021.20056 or earlier, system is vulnerable.Check Version:
On Windows: wmic product where name="Adobe Acrobat Reader DC" get versionVerify Fix Applied:
Verify version is 2019.021.20061 or later in Help > About Adobe Acrobat Reader DC.📡 Detection & Monitoring
Log Indicators:
- Adobe Reader crash logs with memory access violations
- Windows Event Logs showing unexpected process creation from AcroRd32.exe
Network Indicators:
- Outbound connections from Adobe Reader process to suspicious IPs
- DNS requests for known exploit domains
SIEM Query:
source="windows" AND process_name="AcroRd32.exe" AND (event_id=1000 OR event_id=1001) AND message="*Access Violation*"