CVE-2019-8100
📋 TL;DR
This vulnerability allows attackers to execute arbitrary code on affected Adobe Acrobat and Reader installations by exploiting an out-of-bounds write memory corruption flaw. Successful exploitation could give attackers full control of the victim's system. Users running vulnerable versions of Adobe Acrobat or Reader are affected.
💻 Affected Systems
- Adobe Acrobat DC
- Adobe Acrobat Reader DC
- Adobe Acrobat 2017
- Adobe Acrobat Reader 2017
- Adobe Acrobat 2015
- Adobe Acrobat Reader 2015
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control, data theft, ransomware deployment, and lateral movement within the network.
Likely Case
Malicious PDF documents delivered via email or web downloads lead to system compromise, credential theft, and malware installation.
If Mitigated
With proper patching and security controls, impact is limited to isolated incidents that can be contained through endpoint detection and response.
🎯 Exploit Status
Exploitation requires user interaction to open a malicious PDF file. The vulnerability has been actively exploited in the wild.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Acrobat DC/Reader DC: 2019.012.20036 or later; Acrobat 2017/Reader 2017: 2017.011.30144 or later; Acrobat 2015/Reader 2015: 2015.006.30499 or later
Vendor Advisory: https://helpx.adobe.com/security/products/acrobat/apsb19-41.html
Restart Required: Yes
Instructions:
1. Open Adobe Acrobat or Reader. 2. Go to Help > Check for Updates. 3. Follow prompts to install available updates. 4. Restart the application when prompted. 5. Verify update by checking Help > About Adobe Acrobat/Reader.
🔧 Temporary Workarounds
Disable JavaScript in Adobe Reader
allDisabling JavaScript reduces attack surface as many PDF exploits rely on JavaScript execution.
Edit > Preferences > JavaScript > Uncheck 'Enable Acrobat JavaScript'
Use Protected View
allEnable Protected View to open untrusted PDFs in sandboxed mode.
Edit > Preferences > Security (Enhanced) > Enable Protected View at startup
🧯 If You Can't Patch
- Implement application whitelisting to block execution of Adobe Reader/Acrobat
- Deploy network segmentation to isolate PDF processing systems from critical assets
🔍 How to Verify
Check if Vulnerable:
Open Adobe Acrobat/Reader, go to Help > About Adobe Acrobat/Reader and compare version number with affected ranges.Check Version:
On Windows: wmic product where "name like 'Adobe%Acrobat%'" get version; On macOS: /usr/libexec/PlistBuddy -c 'Print CFBundleShortVersionString' /Applications/Adobe\ Acrobat\ Reader\ DC.app/Contents/Info.plistVerify Fix Applied:
Check version number is at or above patched versions: 2019.012.20036+, 2017.011.30144+, or 2015.006.30499+📡 Detection & Monitoring
Log Indicators:
- Adobe Reader/Acrobat crash logs with memory access violations
- Windows Event Logs: Application crashes with exception code 0xC0000005 (ACCESS_VIOLATION)
- Process creation from Adobe Reader/Acrobat with suspicious command lines
Network Indicators:
- Outbound connections from Adobe Reader/Acrobat to suspicious IPs
- DNS requests for known exploit kit domains following PDF file access
SIEM Query:
source="*windows*" (event_id=1000 OR event_id=1001) process_name="AcroRd32.exe" OR process_name="Acrobat.exe" exception_code="0xC0000005"