CVE-2025-64786
📋 TL;DR
Acrobat Reader has an improper cryptographic signature verification vulnerability that allows attackers to bypass security features and gain limited unauthorized write access. This affects users of Acrobat Reader versions 24.001.30264, 20.005.30793, 25.001.20982, 24.001.30273, 20.005.30803 and earlier. Exploitation requires no user interaction.
💻 Affected Systems
- Adobe Acrobat Reader DC
- Adobe Acrobat Reader
📦 What is this software?
Acrobat by Adobe
Acrobat by Adobe
Acrobat by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Attacker could modify system files or configuration data, potentially leading to privilege escalation or persistence mechanisms.
Likely Case
Limited file modification in user-accessible directories, potentially enabling further attacks or data manipulation.
If Mitigated
Impact limited to isolated sandbox environment with proper application sandboxing and file integrity monitoring.
🎯 Exploit Status
Exploitation requires crafting malicious PDFs with improper signatures. No user interaction needed but attacker must deliver payload to target.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update to versions after those listed in affected versions
Vendor Advisory: https://helpx.adobe.com/security/products/acrobat/apsb25-119.html
Restart Required: Yes
Instructions:
1. Open Adobe Acrobat Reader
2. Go to Help > Check for Updates
3. Follow prompts to install available updates
4. Restart computer after installation completes
🔧 Temporary Workarounds
Disable JavaScript in Acrobat Reader
allPrevents JavaScript-based exploitation vectors that might leverage this vulnerability
Edit > Preferences > JavaScript > Uncheck 'Enable Acrobat JavaScript'
Use Protected View for untrusted files
allForces all PDFs from untrusted sources to open in protected mode
Edit > Preferences > Security (Enhanced) > Check 'Enable Protected View at startup' and 'Enable Protected View for files originating from the Internet'
🧯 If You Can't Patch
- Implement application whitelisting to prevent unauthorized Acrobat Reader execution
- Deploy file integrity monitoring to detect unauthorized file modifications
🔍 How to Verify
Check if Vulnerable:
Check Help > About Adobe Acrobat Reader DC and compare version against affected listCheck Version:
On Windows: "C:\Program Files\Adobe\Acrobat Reader DC\Reader\AcroRd32.exe" /? | find "Version"Verify Fix Applied:
Verify version is newer than affected versions and check that updates were successfully installed📡 Detection & Monitoring
Log Indicators:
- Unexpected file modification events in Acrobat Reader directories
- Multiple failed signature verification attempts in application logs
Network Indicators:
- Unusual PDF downloads from untrusted sources
- PDF files with modified signatures
SIEM Query:
source="*acrobat*" AND (event_type="file_modification" OR message="signature verification")