CVE-2026-54651

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/py-pdf/pypdf/pull/3839	Issue Tracking
https://github.com/py-pdf/pypdf/releases/tag/6.13.1	Patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcj	Mitigation Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*

History

24 Jun 2026, 16:41

Type	Values Removed	Values Added
First Time		Pypdf Project Pypdf Project pypdf
References	~~() https://github.com/py-pdf/pypdf/pull/3839 -~~	() https://github.com/py-pdf/pypdf/pull/3839 - Issue Tracking
References	~~() https://github.com/py-pdf/pypdf/releases/tag/6.13.1 -~~	() https://github.com/py-pdf/pypdf/releases/tag/6.13.1 - Patch
References	~~() https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcj -~~	() https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcj - Mitigation, Patch, Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5
CPE		cpe:2.3:a:pypdf_project:pypdf::::::::

22 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 21:16

Updated : 2026-06-24 16:41

NVD link : CVE-2026-54651

Mitre link : CVE-2026-54651

CVE.ORG link : CVE-2026-54651

JSON object : View

Products Affected

pypdf_project

pypdf

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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