CVE-2026-84309
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.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 6.9
- CVSS vector
- CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- EPSS probability
- 0.13%
- CWE
- CWE-835
- Published
- 2026-09-01
- Last modified
- 2026-09-02
Affected products
- py-pdf pypdf
Weakness type
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