Is CVE-2026-100844 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-100844 being exploited in the wild.

How severe is CVE-2026-100844?

High severity, with a CVSS score of 8.4, published 27 September 2026.

Which products and versions are affected?

Project-MONAI MONAI before 1.6.0; monai (PyPI) ECOSYSTEM:introduced=0,fixed=1.6.0.

Is there a fix for CVE-2026-100844?

Yes. monai (PyPI): upgrade to 1.6.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-100844 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-100844?

Check whether you run Project-MONAI MONAI or monai (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-2026-100844: MONAI OS command injection in nnUNetV2Runner

CVE-2026-100844 · Severity: high · CVSS 8.4 · Published 2026-09-27

MONAI is a deep learning framework used for medical image analysis and training neural network models. A vulnerability in its nnUNetV2Runner component allows attackers to execute arbitrary operating system commands by injecting shell metacharacters into configuration files or command-line arguments. An attacker who tricks a user into loading a malicious YAML configuration file can gain full control of the system with the privileges of the user running the training job.

Technologies: Project-MONAI MONAI, monai (PyPI). Vendors: Project-MONAI, PyPI.

Quick answers

Is CVE-2026-100844 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-100844 being exploited in the wild.
How severe is CVE-2026-100844?: High severity, with a CVSS score of 8.4, published 27 September 2026.
Which products and versions are affected?: Project-MONAI MONAI before 1.6.0; monai (PyPI) ECOSYSTEM:introduced=0,fixed=1.6.0.
Is there a fix for CVE-2026-100844?: Yes. monai (PyPI): upgrade to 1.6.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-100844 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-100844?: Check whether you run Project-MONAI MONAI or monai (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

monai (PyPI): upgrade to 1.6.0 or later
```
pip install "monai>=1.6.0"
```

Technical details

OS command injection in nnUNetV2Runner via unsanitized user input (dataset_name_or_id from YAML config or CLI/kwargs arguments) concatenated into shell commands and executed with subprocess shell=True. Attack vector is local; user must load a crafted YAML configuration file and invoke training/validation functions (e.g., train_single_model()). No privileges or network access required; arbitrary code execution with user privileges.

Affected products

Project-MONAI MONAI before 1.6.0

Identifiers

CVE-2026-100844
GHSA-rghg-q7wp-9767
PYSEC-2026-4019

Timeline

2026-09-27: disclosed
2026-06-11: patched: Version 1.6.0 released with patch

References

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