Deserialization in Pdfminer Pdfminer.six

CVE-2025-64512

Pdfminer.six is a community maintained fork of the original PDFMiner, a tool for extracting information from PDF documents. Prior to version 20251107, pdfminer.six will execute arbitrary code from a malicious pickle file if provided with a malicious PDF file. The `CMapDB._load_data()` function in pdfminer.six uses `pickle.loads()` to deserialize pickle files. These pickle files are supposed to be part of the pdfminer.six distribution stored in the `cmap/` directory, but a malicious PDF can specify an alternative directory and filename as long as the filename ends in `.pickle.gz`. A malicious, zipped pickle file can then contain code which will automatically execute when the PDF is processed. Version 20251107 fixes the issue.

Vulnerability class: Insecure Deserialization

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (21.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-64512: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-64512?
CVE-2025-64512 is a high-severity vulnerability in Pdfminer Pdfminer.six, classified under Deserialization of Untrusted Data. CVSS score: 8.6/10. Published 2025-11-10.
How severe is CVE-2025-64512?
High severity. CVSS v3 base score is 8.6 out of 10.
Is CVE-2025-64512 known to be exploited?
11 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.