CVE-2025-6544: H2O Deserialization Vulnerability Leading to Arbitrary Code Execution
Summary
CVE-2025-6544: H2O affected by a deserialization vulnerability. Affects h2o versions < 3.46.0.7. No fix is published. How to fix ↓
Also tracked for
- ai.h2o:h2o-core · Maven
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 designed for data analysis and predictive modeling. It provides a user-friendly interface and supports various algorithms for data processing. However, versions of H2O up to 3.46.0.7 are vulnerable to a deserialization issue that can be exploited by attackers, potentially compromising system security.
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. The ramifications include unauthorized access to sensitive data and the ability to execute malicious code on the affected system.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
As a temporary workaround, avoid using JDBC connection parameters that could be manipulated. Ensure that any user inputs are properly sanitized and validated to prevent exploitation of this vulnerability.
Conclusion
The deserialization vulnerability in H2O poses a serious risk to users of affected versions. It is crucial to update to the latest version to mitigate potential security threats. Regular monitoring of dependencies using tools like Vulert can help maintain the security of your applications.
See every vulnerability recorded for h2o →
FAQ
The CVSS score of this vulnerability is 9.8, indicating a critical level of severity.
All versions of H2O up to and including 3.46.0.7 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 requiring any signup.
Exploitation of this vulnerability can lead to unauthorized access to system files and execution of arbitrary code, posing significant security risks.
Yes, Vulert can monitor and alert you in real-time for open-source vulnerabilities in your software using just the Pipfile.lock.
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