Vulnerability in Py-Pdf Pypdf
CVE-2026-41168
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large `/Size` values or object streams with wrong large `/N` values. This has been fixed in pypdf 6.10.1. As a workaround, one may apply the changes from the patch manually.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.005 (42.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 42.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Py-Pdf Pypdf — versions < 6.10.1
- Pypdf Project
Weakness classification (CWE)
References
- github.com/py-pdf/pypdf/security/advisories/GHSA-jj6c-8h6c-hppx (Patch, Mitigation, Vendor Advisory)
- github.com/py-pdf/pypdf/pull/3733 (Patch, Issue Tracking)
- github.com/py-pdf/pypdf/commit/62338e9d36419cf193ccec7331784f45df1d70b3 (Patch)
- github.com/py-pdf/pypdf/releases/tag/6.10.1 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-41168?
- CVE-2026-41168 is a medium-severity vulnerability in Py-Pdf Pypdf, classified under Excessive Iteration. CVSS score: 5.3/10. Published 2026-04-22.
- How severe is CVE-2026-41168?
- Medium severity. CVSS v3 base score is 5.3 out of 10.