---
id: CVE-2026-100844
title: >-
  MONAI before 1.6.0 is vulnerable to OS command injection in the nnUNetV2Runner
  component (monai.apps.nnunet.nnunetv2_runner)
summary: >-
  MONAI before 1.6.0 is vulnerable to OS command injection in the nnUNetV2Runner
  component (monai.apps.nnunet.nnunetv2_runner). User-controlled values taken
  from the YAML configuration file (notably dataset_name_or_id) and from
  CLI/kwargs …
severity: high
cvss: 8.4
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-78
vendor: Project-MONAI
product: MONAI
affected:
  - MONAI < 1.6.0
published: '2026-09-27'
updated: '2026-09-27'
sourceUpdated: '2026-09-27T02:17:22.993'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100844'
references:
  - url: >-
      https://github.com/Project-MONAI/MONAI/security/advisories/GHSA-rghg-q7wp-9767
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/monai-before-1.6.0-os-command-injection-via-dataset-name-or-id
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-27T02:41:45.574Z'
---

## Overview

MONAI before 1.6.0 is vulnerable to OS command injection in the nnUNetV2Runner component (monai.apps.nnunet.nnunetv2_runner). User-controlled values taken from the YAML configuration file (notably dataset_name_or_id) and from CLI/kwargs arguments are concatenated into a command string without quoting or validation and then passed to subprocess with shell=True, so shell metacharacters (e.g., ';' on Linux, '&' on Windows) are interpreted. If a victim loads and processes a crafted configuration file — for example by instantiating nnUNetV2Runner with the malicious YAML and invoking a training/validation job such as train_single_model() — arbitrary commands are executed with the privileges of the user running the job.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.