CVE-2025-66019

pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/py-pdf/pypdf/commit/96186725e5e6f237129a58a97cd19204a9ce40b2
https://github.com/py-pdf/pypdf/releases/tag/6.4.0
https://github.com/py-pdf/pypdf/security/advisories/GHSA-m449-cwjh-6pw7
https://aydinnyunus.github.io/2025/12/20/cve-2025-66019-pypdf-lzw-dos/

Configurations

No configuration.

History

19 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) pypdf es una biblioteca PDF de Python puro, gratuita y de código abierto. Versiones anteriores a la versión 6.4.0, un atacante que utiliza esta vulnerabilidad puede crear un PDF que conduce a un uso de memoria de hasta 1 GB por flujo. Esto requiere analizar el flujo de contenido de una página utilizando el filtro LZWDecode. Este problema ha sido parcheado en la versión 6.4.0.

Information

Published : 2025-11-26 00:15

Updated : 2026-10-19 13:10

NVD link : CVE-2025-66019

Mitre link : CVE-2025-66019

CVE.ORG link : CVE-2025-66019

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

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