Is CVE-2026-119205 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-119205 being exploited in the wild.

How severe is CVE-2026-119205?

High severity, with a CVSS score of 4, published 29 October 2026.

Which products and versions are affected?

Py-Pdf Pypdf before 6.21.4; pypdf (PyPI) < 6.21.4, ECOSYSTEM:introduced=0,fixed=6.21.4.

Is there a fix for CVE-2026-119205?

Yes. pypdf (PyPI): upgrade to 6.21.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-119205 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-119205?

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-2026-119205: pypdf infinite loop in DictionaryObject cloning

Q: Is there a fix for CVE-2026-119205?

Yes. pypdf (PyPI): upgrade to 6.21.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-119205 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-119205?

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-2026-119205 · Severity: high · CVSS 4 · Published 2026-10-29

pypdf is a Python library for reading and writing PDF files. A vulnerability allows a specially crafted PDF with cyclic references to cause pypdf to enter an infinite loop when cloning or duplicating the PDF structure, potentially causing a denial of service by consuming CPU and memory.

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

Quick answers

Is CVE-2026-119205 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-119205 being exploited in the wild.
How severe is CVE-2026-119205?: High severity, with a CVSS score of 4, published 29 October 2026.
Which products and versions are affected?: Py-Pdf Pypdf before 6.21.4; pypdf (PyPI) < 6.21.4, ECOSYSTEM:introduced=0,fixed=6.21.4.
Is there a fix for CVE-2026-119205?: Yes. pypdf (PyPI): upgrade to 6.21.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-119205 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-119205?: 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 6.21.4 or later
```
pip install "pypdf>=6.21.4"
```

Technical details

The vulnerability exists in the DictionaryObject cloning logic, where cycle detection checked the indirect references of cloned (destination) objects rather than the original source objects. This allowed certain cycles in the source PDF to bypass the visited-object check. The fix changes the cycle detection to track source object references instead of cloned references.

Affected products

py-pdf pypdf before 6.21.4

Identifiers

CVE-2026-119205
GHSA-mfr5-77xh-9j7h

Timeline

2026-10-29: disclosed
2026-10-28: patched

References

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