CVE-2026-41313

pypdf: Possible long runtimes for wrong size values in incremental mode

Description

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.

Scores

Weaknesses (CWE)

• CWE-834

Advisories

• GHSA-4pxv-j86v-mhcw — pypdf: Possible long runtimes for wrong size values in incremental mode
• PYSEC-2026-3007 — pypdf: Possible long runtimes for wrong size values in incremental mode

European references

• ENISA EUVD · EUVD-2026-25114
• GCVE · GCVE-0-2026-41313

CERT-FR advisories

• CERTFR-2026-AVI-0698 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

• cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:* < 6.10.2

Affected products

References

• https://github.com/py-pdf/pypdf/security/advisories/GHSA-4pxv-j86v-mhcw
• https://github.com/py-pdf/pypdf/pull/3735
• https://github.com/py-pdf/pypdf/commit/c50a0104cf083356f7c7f5d61410466a57f5c88a
• https://github.com/py-pdf/pypdf/releases/tag/6.10.2

Sources