CVE-2025-6544: H2O Deserialization Vulnerability Allows Arbitrary Code Execution
Summary
CVE-2025-6544: H2O affected by a deserialization vulnerability. Affects ai.h2o:h2o-core versions < 3.46.0.7. No fix is published. How to fix ↓
Also tracked for
- h2o · PyPI
The same CVE-2025-6544 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
H2O is an open-source machine learning platform that provides a suite of algorithms for data analysis and predictive modeling. It is widely used for its ability to handle large datasets efficiently and its support for various programming languages, including R and Python. The platform's core component, h2o-core, is essential for its functionality, enabling users to build and deploy machine learning models. However, a critical deserialization vulnerability has been identified in versions up to 3.46.0.7, which poses significant risks to users.
Vulnerability Detail
A deserialization vulnerability exists in h2oai/h2o-3 versions <= 3.46.0.7, allowing attackers to read arbitrary system files and execute arbitrary code. This vulnerability arises from improper handling of JDBC connection parameters, which can be exploited by bypassing regular expression checks and using double URL encoding. Attackers can leverage this flaw to gain unauthorized access to sensitive information and potentially take control of the affected systems.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
As a temporary measure, users can restrict access to the application and monitor for any suspicious activity until the package is updated. Additionally, avoid using JDBC connection parameters that could be manipulated.
Conclusion
The deserialization vulnerability in H2O poses a significant risk to users of the affected versions. It is crucial to update to the latest version to mitigate potential threats. Users are encouraged to monitor their applications and utilize tools like Vulert for real-time vulnerability alerts.
See every vulnerability recorded for ai.h2o:h2o-core →
FAQ
CVE-2025-6544 is a critical deserialization vulnerability in the H2O machine learning platform that allows attackers to execute arbitrary code.
The vulnerability affects H2O versions up to 3.46.0.7.
You can use Vulert's playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
The CVSS score of this vulnerability is 9.8, indicating a critical severity level.
If you cannot update the package immediately, implement access restrictions and monitor for any unusual activities as a temporary workaround.
Related vulnerabilities
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