CVE-2026-84309

EUVD-2026-69477
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.
Infinite Loop
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.5 MEDIUM
LOCAL
LOW
NONE
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 7.72%
Affected Products (NVD)
VendorProductVersion
pypdf_projectpypdf
𝑥
< 6.16.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
pypdf
bookworm
postponed
forky
6.19.0-1
fixed
sid
6.19.0-1
fixed
trixie
no-dsa
pypdf2
bookworm
postponed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
pypdf
jammy
dne
noble
needs-triage
resolute
needs-triage
Common Weakness Enumeration
References
https://github.com/py-pdf/pypdf/commit/c9ba557d565d57c53a0b3a0be06c0a4c29b0559b
https://github.com/py-pdf/pypdf/pull/3964
https://github.com/py-pdf/pypdf/releases/tag/6.16.0
https://github.com/py-pdf/pypdf/security/advisories/GHSA-jp53-mhqp-8xcg