Medium 5.5Published Jun 22, 2026

CVE-2026-54651pypdf is a free and open-source pure-python PDF library.

Updated under an hour ago (2026-10-19 10:00 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for pypdf_project pypdf

Exploited in the last 30 days

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: 5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-835
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jun 24, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

pypdf_project pypdf pypdf_project:pypdf	before 6.13.1	NVD

References

https://github.com/py-pdf/pypdf/pull/3839issue-tracking
https://github.com/py-pdf/pypdf/releases/tag/6.13.1patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcjmitigation, patch, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.