CVE-2026-27628

pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams

Published: Feb 25, 2026Updated: Feb 27, 2026 Sources: CVE List NVD GHSA BDUCWE-835

7.5HIGH

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.7.2, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. This has been fixed in pypdf 6.7.2. As a workaround, one may apply the patch manually.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-835

Affected Products

Red Hat Inc.

commercial·USaka red hat

Red Hat OpenShift LightspeedOn-prem

Operating Systems / linux-distro

Red Hat QuayOn-prem

Operating Systems / linux-distro

Red Hat OpenShift AIOn-prem

Operating Systems / linux-distro

pypdf project

oss-project

pypdfLibrary

OSS Libraries / generic-library

package-ecosystem

commercial·RUaka red soft

РЕД ОСOn-premOS

Operating Systems / linux-distro

Matthew Peveler

aka pypdf2

PyPDF2Library

OSS Libraries

py-pdf

package-ecosystemaka pypdf, pypdf2

pypdfOn-prem

OSS Libraries / pypi

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Impact

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References

https://github.com/py-pdf/pypdf/commit/f0a462d36971cf077d74492a348d0d06fd60ea4d

github.com

https://github.com/py-pdf/pypdf/issues/3654

github.com

https://github.com/py-pdf/pypdf/security/advisories/GHSA-2rw7-x74f-jg35

github.com

and 9 more references View all →

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