CVE-2025-64512
📋 TL;DR
CVE-2025-64512 is a remote code execution vulnerability in pdfminer.six where malicious PDF files can trigger deserialization of arbitrary pickle files, leading to arbitrary code execution. This affects any application or service that processes PDF files using vulnerable versions of pdfminer.six. The vulnerability is particularly dangerous because it can be exploited without user interaction in automated PDF processing systems.
💻 Affected Systems
- pdfminer.six
📦 What is this software?
Pdfminer.six by Pdfminer
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining complete control over the affected system, enabling data theft, lateral movement, and persistent backdoor installation.
Likely Case
Arbitrary code execution in the context of the PDF processing application, potentially leading to data exfiltration, cryptocurrency mining, or ransomware deployment.
If Mitigated
Limited impact if proper sandboxing and least privilege principles are implemented, potentially restricting damage to isolated containers or limited user contexts.
🎯 Exploit Status
The vulnerability is straightforward to exploit with a specially crafted PDF file. Public proof-of-concept code exists in the advisory references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 20251107
Vendor Advisory: https://github.com/pdfminer/pdfminer.six/security/advisories/GHSA-wf5f-4jwr-ppcp
Restart Required: No
Instructions:
1. Update pdfminer.six to version 20251107 or later using pip: 'pip install --upgrade pdfminer.six>=20251107' 2. Verify the update with: 'pip show pdfminer.six' 3. Restart any services or applications using pdfminer.six to ensure they load the patched version.
🔧 Temporary Workarounds
Restrict PDF Processing
allTemporarily disable PDF processing in affected applications until patching is complete.
Sandbox PDF Processing
linuxRun pdfminer.six in isolated containers or sandboxed environments with minimal privileges.
docker run --read-only --cap-drop=ALL -v /tmp:/tmp:ro your_application
🧯 If You Can't Patch
- Implement strict input validation to reject PDF files with suspicious CMap references or pickle file paths.
- Deploy runtime application self-protection (RASP) or WAF rules to detect and block exploitation attempts targeting pickle deserialization.
🔍 How to Verify
Check if Vulnerable:
Check the installed version of pdfminer.six: 'pip show pdfminer.six | grep Version' - if version is earlier than 20251107, the system is vulnerable.Check Version:
pip show pdfminer.six | grep VersionVerify Fix Applied:
Verify the version is 20251107 or later: 'pip show pdfminer.six | grep Version' should show 'Version: 20251107' or higher.📡 Detection & Monitoring
Log Indicators:
- Unusual process execution from PDF processing services
- Errors related to pickle deserialization or CMap loading
- Outbound connections from PDF processing systems to unknown IPs
Network Indicators:
- Unexpected outbound network traffic from PDF processing systems
- DNS requests to suspicious domains from PDF processing services
SIEM Query:
source="pdfminer" AND (event="pickle.loads" OR event="CMapDB._load_data")🔗 References
- https://github.com/pdfminer/pdfminer.six/commit/b808ee05dd7f0c8ea8ec34bdf394d40e63501086
- https://github.com/pdfminer/pdfminer.six/releases/tag/20251107
- https://github.com/pdfminer/pdfminer.six/security/advisories/GHSA-wf5f-4jwr-ppcp
- https://lists.debian.org/debian-lts-announce/2025/11/msg00017.html
- https://lists.debian.org/debian-lts-announce/2026/01/msg00005.html
- https://github.com/pdfminer/pdfminer.six/security/advisories/GHSA-wf5f-4jwr-ppcp
