CVE-2026-59937

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.

CVSS 4.0

6.9CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS 3.1

7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

0.6% chance of exploitation in the next 30 days; higher than 49% of CVEs (scores of 2026-10-25)

CWE

CWE-400

Published

2026-07-08

Modified

2026-10-25

Record from

the NVD, synced 2026-10-25

Affected

• pypdf_project:pypdf

Packages (OSV)

References

• https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50dae
• https://github.com/py-pdf/pypdf/pull/3887
• https://github.com/py-pdf/pypdf/releases/tag/6.14.0
• https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37v

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