CVE-2026-84309
pypdf: Possible infinite loop for TreeObject.insert_child
Description
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.
No summary for this CVE yet.
Weaknesses
Affected Products
py-pdf
package-ecosystemaka pypdf, pypdf2
pypdfOn-prem
OSS Libraries / pypiExploitability
No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Impact
References
https://github.com/py-pdf/pypdf/commit/c9ba557d565d57c53a0b3a0be06c0a4c29b0559b
github.com
https://github.com/py-pdf/pypdf/pull/3964
github.com
https://github.com/py-pdf/pypdf/releases/tag/6.16.0
github.com
and 1 more references View all →
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