CVE-2026-54531

MEDIUM

pypdf: Possible infinite loop when processing outlines/bookmarks in writer

Title source: cna
STIX 2.1

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.13.0, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with outlines into a writer. This vulnerability is fixed in 6.13.0.

References (3)

Core 3
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/pull/3830
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/releases/tag/6.13.0

Scores

CVSS v3 5.5
EPSS 0.0012
EPSS Percentile 2.3%
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 yes
Technical Impact partial

Details

CWE
CWE-835
Status published
Products (2)
py-pdf/pypdf < 6.13.0
pypdf_project/pypdf < 6.13.0
Published Jun 22, 2026
Tracked Since Jun 23, 2026