CVE-2026-84309

UNKNOWN 0.0

pypdf: Possible infinite loop for TreeObject.insert_child

CVSS Score

0.0

EPSS Score

0.0%

EPSS Percentile

0th

pypdf is a free and open-source pure-python PDF library. Prior to 6.16.0, an attacker can craft a PDF whose cyclic tree structure causes pypdf/generic/_data_structures.py TreeObject.insert_child to follow /Next links indefinitely when a writing code path inserts a child, producing an infinite loop. This issue is fixed in version 6.16.0.

CWE	CWE-835
Vendor	py-pdf
Product	pypdf
Published	Sep 1, 2026

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Affected Versions

py-pdf / pypdf

< 6.16.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/py-pdf/pypdf/security/advisories/GHSA-jp53-mhqp-8xcg github.com: https://github.com/py-pdf/pypdf/pull/3964 github.com: https://github.com/py-pdf/pypdf/commit/c9ba557d565d57c53a0b3a0be06c0a4c29b0559b github.com: https://github.com/py-pdf/pypdf/releases/tag/6.16.0