CVE-2023-26425
📋 TL;DR
Adobe Acrobat Reader versions 23.001.20093 and earlier, and 20.005.30441 and earlier, contain an out-of-bounds read vulnerability when parsing malicious PDF files. An attacker could exploit this to execute arbitrary code with the privileges of the current user. Exploitation requires user interaction, such as opening a malicious file.
💻 Affected Systems
- Adobe Acrobat Reader DC
- Adobe Acrobat Reader
📦 What is this software?
Acrobat by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise via arbitrary code execution with user privileges, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Limited code execution in user context, potentially enabling malware installation or credential theft from the affected user account.
If Mitigated
No impact if users avoid opening untrusted PDF files or if security controls block malicious files.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file). No public exploit code is known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 23.001.20174 and later for continuous track, 20.005.30516 and later for classic track
Vendor Advisory: https://helpx.adobe.com/security/products/acrobat/apsb23-24.html
Restart Required: Yes
Instructions:
1. Open Adobe Acrobat Reader. 2. Go to Help > Check for Updates. 3. Follow prompts to install latest version. 4. Restart computer after installation.
🔧 Temporary Workarounds
Disable JavaScript in Adobe Reader
allPrevents JavaScript-based exploitation vectors
Edit > Preferences > JavaScript > Uncheck 'Enable Acrobat JavaScript'
Use Protected View for untrusted files
allOpens files in sandboxed mode by default
Edit > Preferences > Security (Enhanced) > Check 'Enable Protected View at startup'
🧯 If You Can't Patch
- Block PDF files from untrusted sources at email/web gateways
- Implement application whitelisting to prevent unauthorized PDF readers
🔍 How to Verify
Check if Vulnerable:
Check Adobe Reader version: Help > About Adobe Acrobat Reader DCCheck Version:
Windows: wmic product where name="Adobe Acrobat Reader DC" get versionVerify Fix Applied:
Verify version is 23.001.20174 or higher (continuous) or 20.005.30516 or higher (classic)📡 Detection & Monitoring
Log Indicators:
- Adobe Reader crash logs with memory access violations
- Windows Event Logs: Application crashes from AcroRd32.exe
Network Indicators:
- Unusual outbound connections after opening PDF files
- Downloads of suspicious PDF files from external sources
SIEM Query:
source="*acrobat*" AND (event_id=1000 OR event_id=1001) AND process_name="AcroRd32.exe"