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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/py-pdf/pypdf/releases/tag/6.13.1 Patch
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcj Mitigation, Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 6.9 · pypdf_projectNVD modified 2026-10-25 23:10
Affected (CPE criteria) 1
cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*
References 3
- https://github.com/py-pdf/pypdf/pull/3839 Issue Tracking
- https://github.com/py-pdf/pypdf/releases/tag/6.13.1 Patch
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9xf-7f8q-9mcj Mitigation, Patch, Vendor Advisory