CVE-2021-44707
📋 TL;DR
This CVE describes an out-of-bounds write vulnerability in Adobe Acrobat Reader DC that could allow arbitrary code execution when a user opens a malicious PDF file. Attackers can exploit this to run code with the victim's user privileges, potentially compromising the system. All users running affected versions of Acrobat Reader DC are at risk.
💻 Affected Systems
- Adobe Acrobat Reader DC
📦 What is this software?
Acrobat by Adobe
Acrobat by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining complete control over the victim's computer, data theft, ransomware deployment, and lateral movement within the network.
Likely Case
Malware installation, credential theft, and data exfiltration from the compromised user's account.
If Mitigated
Limited impact with only the user's session affected if proper application sandboxing and privilege separation are in place.
🎯 Exploit Status
Exploitation requires user interaction (opening a malicious file). No public proof-of-concept has been disclosed as of the advisory date.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 21.007.20099 (update to 21.007.20099 or later for version 21.x), 20.004.30017 (update to 20.004.30017 or later for version 20.x), 17.011.30204 (update to 17.011.30204 or later for version 17.x)
Vendor Advisory: https://helpx.adobe.com/security/products/acrobat/apsb22-01.html
Restart Required: Yes
Instructions:
1. Open Adobe Acrobat Reader DC. 2. Go to Help > Check for Updates. 3. Follow the prompts to download and install the latest version. 4. Restart the application when prompted.
🔧 Temporary Workarounds
Disable JavaScript in Adobe Reader
allDisabling JavaScript can prevent exploitation of some PDF-based vulnerabilities
Edit > Preferences > JavaScript > Uncheck 'Enable Acrobat JavaScript'
Use Protected View
allEnable Protected View to open untrusted PDFs in a sandboxed environment
Edit > Preferences > Security (Enhanced) > Enable Protected View at startup
🧯 If You Can't Patch
- Restrict user permissions to prevent installation of malicious software
- Implement application whitelisting to block unauthorized executables
🔍 How to Verify
Check if Vulnerable:
Check Adobe Acrobat Reader DC version in Help > About Adobe Acrobat Reader DCCheck Version:
On Windows: wmic product where name="Adobe Acrobat Reader DC" get versionVerify Fix Applied:
Verify version is 21.007.20099 or later (21.x), 20.004.30017 or later (20.x), or 17.011.30204 or later (17.x)📡 Detection & Monitoring
Log Indicators:
- Unusual process creation from AcroRd32.exe
- Crash logs from Adobe Reader with memory access violations
Network Indicators:
- Unexpected outbound connections from Adobe Reader process
- Downloads of PDF files from untrusted sources
SIEM Query:
Process Creation where Image contains "AcroRd32.exe" and CommandLine contains suspicious parameters