Description
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.
Scores
CVSS v3
5.1
EPSS
0.0009
EPSS Percentile
25.1%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:H/PR:N/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 (2)
pypdf_project/pypdf
3.7.0 - 3.17.0
pypi/pypdf
3.7.0 - 3.17.0PyPI
Published
Oct 31, 2023
Tracked Since
Feb 18, 2026