CVE-2026-33123

pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.1 allow an attacker to craft a malicious PDF which leads to long runtimes and/or large memory usage. Exploitation requires accessing an array-based stream with many entries. This issue has been fixed in version 6.9.1.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/py-pdf/pypdf/pull/3686	Issue Tracking Patch
https://github.com/py-pdf/pypdf/releases/tag/6.9.1	Product Release Notes
https://github.com/py-pdf/pypdf/security/advisories/GHSA-qpxp-75px-xjcp	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*

History

23 Mar 2026, 15:48

Type	Values Removed	Values Added
Summary		(es) pypdf es una biblioteca PDF de Python puro, gratuita y de código abierto. Las versiones anteriores a la 6.9.1 permiten a un atacante crear un PDF malicioso que provoca tiempos de ejecución prolongados y/o un gran uso de memoria. La explotación requiere acceder a un flujo basado en arrays con muchas entradas. Este problema ha sido solucionado en la versión 6.9.1.
First Time		Pypdf Project Pypdf Project pypdf
References	~~() https://github.com/py-pdf/pypdf/pull/3686 -~~	() https://github.com/py-pdf/pypdf/pull/3686 - Issue Tracking, Patch
References	~~() https://github.com/py-pdf/pypdf/releases/tag/6.9.1 -~~	() https://github.com/py-pdf/pypdf/releases/tag/6.9.1 - Product, Release Notes
References	~~() https://github.com/py-pdf/pypdf/security/advisories/GHSA-qpxp-75px-xjcp -~~	() https://github.com/py-pdf/pypdf/security/advisories/GHSA-qpxp-75px-xjcp - Patch, Vendor Advisory
CPE		cpe:2.3:a:pypdf_project:pypdf::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.5

20 Mar 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-20 10:16

Updated : 2026-03-23 15:48

NVD link : CVE-2026-33123

Mitre link : CVE-2026-33123

CVE.ORG link : CVE-2026-33123

JSON object : View

Products Affected

pypdf_project

pypdf

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-407

Inefficient Algorithmic Complexity

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