CVE-2026-40260

Description

pypdf is a free and open-source pure-python PDF library. In versions prior to 6.10.0, manipulated XMP metadata entity declarations can exhaust RAM. An attacker who exploits this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the XMP metadata. This issue has been fixed in version 6.10.0.

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

0.0002

Probability of exploitation

0.05%

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-776 CWE-776

Affected Products

Vendor	Product	Versions
pypdf_project	pypdf	< 6.10.0

References

Advisories & Patches

https://github.com/py-pdf/pypdf/commit/b15a374e5ca648d4878e57c3b2c0551e7f8cc7f8 https://github.com/py-pdf/pypdf/pull/3724 https://github.com/py-pdf/pypdf/security/advisories/GHSA-3crg-w4f6-42mx

Other References

https://github.com/py-pdf/pypdf/releases/tag/6.10.0

Frequently Asked Questions

What is CVE-2026-40260? +

pypdf is a free and open-source pure-python PDF library. In versions prior to 6.10.0, manipulated XMP metadata entity declarations can exhaust RAM. An attacker who exploits this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the XMP metadata. This issue has been fixed in version 6.10.0. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2026-40260? +

CVE-2026-40260 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 0.0002, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-40260? +

CVE-2026-40260 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-2026-40260? +

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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