CVE-2026-100846: MONAI Package Arbitrary Code Execution via Untrusted Data Deserialization
Summary
CVE-2026-100846: MONAI before 1.5.2 contains a deserialization of untrusted data vulnerability in the algo_from_pickle function in monai/auto3dseg/utils.py. Affects monai versions < 1.5.2. Fixed in 1.5.2. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
MONAI is an open-source framework designed for medical imaging applications, providing tools and libraries to facilitate deep learning workflows. It is widely used in the healthcare sector for tasks such as image segmentation and analysis. However, prior to version 1.5.2, MONAI contained a vulnerability that allowed for the deserialization of untrusted data, potentially leading to severe security risks.
Vulnerability Detail
The vulnerability arises from the algo_from_pickle function located in monai/auto3dseg/utils.py, which processes .pkl files without validating their source or content. When an attacker supplies a malicious pickle file, the function can execute arbitrary code during deserialization due to the presence of an object defining reduce. This can lead to unauthorized actions within the application, compromising its integrity and security.
How To Fix
Minimum fixed version
1.5.2
This is the first release that contains the fix.
pip install --upgrade "monai==1.5.2"Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, avoid using the algo_from_pickle function with untrusted or unknown pickle files. Implement strict validation of the source and content of any pickle files before processing them.
Conclusion
The MONAI package has a critical vulnerability that allows for arbitrary code execution through the deserialization of untrusted data. It is essential to update to version 1.5.2 or later to mitigate this risk. Users should also exercise caution when handling pickle files and validate their sources.
See every vulnerability recorded for monai →
FAQ
The CVSS score of this vulnerability is 8.8, indicating a high severity level.
Versions of MONAI prior to 1.5.2 are affected by this vulnerability.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
If you cannot update the package immediately, ensure that you do not use the algo_from_pickle function with untrusted data and validate any pickle files before processing.
More information about MONAI and its vulnerabilities can be found on its official GitHub repository and security advisory pages.
References
Related vulnerabilities
Recent vulnerabilities recorded for monai.
