pypdf is a free and open-source pure-python PDF library. Prior to 6.12.2, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /FlateDecode filter with a PNG predictor. This vulnerability is fixed in 6.12.2.
Fix
Patch, vendor advisory and mitigation references on NVD 3
- https://github.com/py-pdf/pypdf/pull/3806 Issue Tracking, Patch
- https://github.com/py-pdf/pypdf/releases/tag/6.12.2 Patch, Release Notes
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-5hgr-hg42-57jg 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 5.1 · 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/3806 Issue Tracking, Patch
- https://github.com/py-pdf/pypdf/releases/tag/6.12.2 Patch, Release Notes
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-5hgr-hg42-57jg Patch, Vendor Advisory