CVE-2026-59936: pypdf: Possible infinite loop for not terminated inline images

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-08 · updated 2026-10-25
Weakness: CWE-400

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.14.1, an attacker can craft a PDF with a page content stream containing a not terminated inline image, causing an infinite loop during inline image end marker detection such as when extracting page text. This issue is fixed in version 6.14.1.

Affected products

py-pdf pypdf: before 6.14.1 — fixed in 6.14.1

How to fix

Upgrade to a fixed version: py-pdf pypdf 6.14.1. Check the vendor advisory for mitigations.

References

https://github.com/py-pdf/pypdf/commit/ec3b14596186c40caca7cf8ab9b2155203e01b5b
https://github.com/py-pdf/pypdf/pull/3891
https://github.com/py-pdf/pypdf/releases/tag/6.14.1
https://github.com/py-pdf/pypdf/security/advisories/GHSA-5xf7-4p34-54qr

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