Vulnerability in Py-Pdf Pypdf

CVE-2026-41313

pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to long runtimes. This requires loading a PDF with a large trailer `/Size` value in incremental mode. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.

EPSS: 0.002 (11.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-41313?
CVE-2026-41313 is a medium-severity vulnerability in Py-Pdf Pypdf, classified under Excessive Iteration. CVSS score: 6.5/10. Published 2026-04-22.
How severe is CVE-2026-41313?
Medium severity. CVSS v3 base score is 6.5 out of 10.