Is CVE-2026-100843 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-100843 being exploited in the wild.

How severe is CVE-2026-100843?

High severity, with a CVSS score of 7.8, 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-2026-100843?

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-2026-100843 attacked?

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

Am I affected by CVE-2026-100843?

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-2026-100843: MONAI remote code execution in algo_from_pickle

CVE-2026-100843 · Severity: high · CVSS 7.8 · Published 2026-09-27

MONAI is a medical imaging framework used in AI-powered diagnostic and analysis workflows. Versions before 1.6.0 contain a flaw that allows attackers to execute arbitrary system commands when processing specially crafted model files, potentially giving an attacker complete control over systems running MONAI pipelines. This is particularly dangerous in healthcare settings where model checkpoints are frequently exchanged between organizations.

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

Quick answers

Is CVE-2026-100843 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-100843 being exploited in the wild.
How severe is CVE-2026-100843?: High severity, with a CVSS score of 7.8, 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-2026-100843?: 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-2026-100843 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-100843?: 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

The vulnerability stems from unsafe pickle.loads() deserialization in monai/auto3dseg/utils.py's algo_from_pickle() function, which deserializes untrusted pickle data without validation. An attacker can craft a malicious pickle file that executes arbitrary code during deserialization. The vulnerability requires local access and user interaction (supply of a file path), but grants full system command execution with the privileges of the process running MONAI.

Affected products

Project-MONAI MONAI before 1.6.0

Identifiers

CVE-2026-100843
GHSA-qxq5-qhx6-94qw
PYSEC-2026-4018

Timeline

2026-06-11: disclosed: GHSA-qxq5-qhx6-94qw published; incomplete fix discovery
2026-01-29: patched: Version 1.6.0 released with complete fix
2026-09-27: advisory: CVE-2026-100843 published

References

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