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CVE-2026-59937

pypdf: Possible long runtimes for repeated malformed cross-reference entries

Published: Jul 8, 2026Updated: Jul 9, 2026 Sources: CVE List NVDCWE-400
7.5HIGH
NVD MITRE
EPSS Score
0.3%
Top 73.3%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with repeated malformed cross-reference streams that cause pypdf to spend long runtimes recovering broken cross-reference table entries. This issue is fixed in version 6.14.0.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
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-400

Affected Products

py-pdf
package-ecosystemaka pypdf, pypdf2
pypdfOn-prem
OSS Libraries / pypi
pypdf project
oss-project
pypdfLibrary
OSS Libraries / generic-library

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37v
github.com
https://github.com/py-pdf/pypdf/pull/3887
github.com
https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50dae
github.com
and 1 more references View all →

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