Is CVE-2026-113790 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-113790 being exploited in the wild.

How severe is CVE-2026-113790?

Medium severity, with a CVSS score of 4, published 21 October 2026.

Which products and versions are affected?

Py-Pdf Pypdf before 6.21.0; pypdf (PyPI) < 6.21.0, ECOSYSTEM:introduced=0,fixed=6.21.0.

Is there a fix for CVE-2026-113790?

Yes. pypdf (PyPI): upgrade to 6.21.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-113790 attacked?

It is attacked over the network.

Am I affected by CVE-2026-113790?

Check whether you run Py-Pdf Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-113790: pypdf resource exhaustion in PDF parsing

Q: Is there a fix for CVE-2026-113790?

Yes. pypdf (PyPI): upgrade to 6.21.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-113790 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-113790?

Check whether you run Py-Pdf Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-113790 · Severity: medium · CVSS 4 · Published 2026-10-21

pypdf is a Python library for reading and manipulating PDF files. An attacker can craft a malicious PDF containing arrays or dictionaries with excessive elements, causing the library to consume large amounts of memory during parsing and potentially causing denial of service or application crashes.

Technologies: Py-Pdf Pypdf, pypdf (PyPI). Vendors: Py-Pdf, PyPI.

Quick answers

Is CVE-2026-113790 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-113790 being exploited in the wild.
How severe is CVE-2026-113790?: Medium severity, with a CVSS score of 4, published 21 October 2026.
Which products and versions are affected?: Py-Pdf Pypdf before 6.21.0; pypdf (PyPI) < 6.21.0, ECOSYSTEM:introduced=0,fixed=6.21.0.
Is there a fix for CVE-2026-113790?: Yes. pypdf (PyPI): upgrade to 6.21.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-113790 attacked?: It is attacked over the network.
Am I affected by CVE-2026-113790?: Check whether you run Py-Pdf Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

pypdf (PyPI): upgrade to 6.21.0 or later
```
pip install "pypdf>=6.21.0"
```

Technical details

The vulnerability is a resource exhaustion issue in pypdf's PDF parsing logic. Prior to version 6.21.0, the library lacked limits on the number of elements in arrays and key-value pairs in dictionaries within PDF streams, allowing crafted PDFs to trigger excessive memory consumption. The fix introduces configurable limits (100,000 elements per array and dictionary) and overall stream parsing work limits to prevent unbounded resource consumption.

Affected products

py-pdf pypdf before 6.21.0

Identifiers

CVE-2026-113790
GHSA-f54x-cmq8-qg57

Timeline

2026-10-16: patched
2026-10-21: disclosed

References

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