CVE-2026-48156

pypdf is a free and open-source pure-python PDF library. Prior to 6.12.0, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size values. This vulnerability is fixed in 6.12.0.

CVSS v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.8 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/py-pdf/pypdf/pull/3791	Issue Tracking Patch
https://github.com/py-pdf/pypdf/releases/tag/6.12.0	Release Notes
https://github.com/py-pdf/pypdf/security/advisories/GHSA-248m-82v9-q6g6	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

29 May 2026, 19:38

Type	Values Removed	Values Added
CPE		cpe:2.3:a:pypdf_project:pypdf::::::::
First Time		Pypdf Project Pypdf Project pypdf
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 3.3
References	~~() https://github.com/py-pdf/pypdf/pull/3791 -~~	() https://github.com/py-pdf/pypdf/pull/3791 - Issue Tracking, Patch
References	~~() https://github.com/py-pdf/pypdf/releases/tag/6.12.0 -~~	() https://github.com/py-pdf/pypdf/releases/tag/6.12.0 - Release Notes
References	~~() https://github.com/py-pdf/pypdf/security/advisories/GHSA-248m-82v9-q6g6 -~~	() https://github.com/py-pdf/pypdf/security/advisories/GHSA-248m-82v9-q6g6 - Patch, Vendor Advisory

28 May 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-28 16:16

Updated : 2026-05-29 19:38

NVD link : CVE-2026-48156

Mitre link : CVE-2026-48156

CVE.ORG link : CVE-2026-48156

JSON object : View

Products Affected

pypdf_project

pypdf

CWE

CWE-834

Excessive Iteration

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