CVE-2026-59938: pypdf — Fix

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with declared image size values that are much too large compared to the actual data, causing large memory usage in pypdf image parsing. This issue is fixed in version 6.14.0.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS — Exploit Prediction

0.0030

Probability of exploitation

0.23%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-789 CWE-789

Affected Products

Vendor	Product	Versions
pypdf_project	pypdf	< 6.14.0

References

Advisories & Patches

https://github.com/py-pdf/pypdf/commit/c64583be16b8e8763d8777075f8ecbf382014b7a https://github.com/py-pdf/pypdf/pull/3888 https://github.com/py-pdf/pypdf/security/advisories/GHSA-5qjq-93h5-hrgp

Other References

https://github.com/py-pdf/pypdf/releases/tag/6.14.0

Frequently Asked Questions

What is CVE-2026-59938? +

pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with declared image size values that are much too large compared to the actual data, causing large memory usage in pypdf image parsing. This issue is fixed in version 6.14.0. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2026-59938? +

CVE-2026-59938 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0030, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-59938? +

CVE-2026-59938 affects products from pypdf_project, specifically: pypdf. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-59938? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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