CVE-2026-33123

UNKNOWN 0.0

pypdf has inefficient decoding of array-based streams

CVSS Score

0.0

EPSS Score

0.0%

EPSS Percentile

2th

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.

CWE	CWE-400 CWE-407
Vendor	py-pdf
Product	pypdf
Published	Mar 20, 2026
Last Updated	Mar 20, 2026

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Affected Versions

py-pdf / pypdf

< 6.9.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/py-pdf/pypdf/security/advisories/GHSA-qpxp-75px-xjcp github.com: https://github.com/py-pdf/pypdf/pull/3686 github.com: https://github.com/py-pdf/pypdf/releases/tag/6.9.1