CVE-2026-54651
MEDIUMpypdf: Possible infinite loop when processing threads/articles in writer
Title source: cnaDescription
pypdf is a free and open-source pure-python PDF library. Prior to 6.13.1, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with threads/articles into a writer. This vulnerability is fixed in 6.13.1.
References (3)
Core 3
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcj
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/pull/3839
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/releases/tag/6.13.1
Scores
CVSS v3
5.5
EPSS
0.0011
EPSS Percentile
1.6%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-835
Status
published
Products (3)
py-pdf/pypdf
< 6.13.1
pypdf_project/pypdf
< 6.13.1
pypi/pypdf
0 - 6.13.1PyPI
Published
Jun 22, 2026
Tracked Since
Jun 23, 2026