EUVD-2025-30380

Comprehensive Technical Analysis of EUVD-2025-30380

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2025-30380 is a deserialization flaw in h2oai/h2o-3 versions <= 3.46.0.8. This vulnerability allows attackers to read arbitrary system files and execute arbitrary code. The severity of this vulnerability is rated with a CVSS Base Score of 9.8, which is considered critical. The CVSS vector (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) indicates the following:

• Attack Vector (AV): Network (N) - The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal skill and resources.
• Privileges Required (PR): None (N) - No special privileges are required to exploit the vulnerability.
• User Interaction (UI): None (N) - No user interaction is required for the attack to succeed.
• Scope (S): Unchanged (U) - The vulnerability affects the same security scope.
• Confidentiality (C): High (H) - The vulnerability allows unauthorized access to sensitive information.
• Integrity (I): High (H) - The vulnerability allows unauthorized modification of data.
• Availability (A): High (H) - The vulnerability can lead to a complete loss of system availability.

2. Potential Attack Vectors and Exploitation Methods

The primary attack vector involves manipulating JDBC connection parameters to bypass regular expression checks and using double URL encoding. This can be achieved through:

• Crafted Inputs: An attacker can send specially crafted inputs to the application that exploit the deserialization process.
• Double URL Encoding: By encoding the input twice, the attacker can bypass security checks and inject malicious payloads.
• Remote Code Execution: Once the input is deserialized, the attacker can execute arbitrary code on the system.

3. Affected Systems and Software Versions

The vulnerability affects all users of h2oai/h2o-3 versions <= 3.46.0.8. This includes any system or application that relies on these versions of the software.

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps should be taken:

• Update Software: Upgrade to a version of h2oai/h2o-3 that is not affected by this vulnerability (version > 3.46.0.8).
• Input Validation: Implement robust input validation and sanitization to prevent malicious inputs from being processed.
• Regular Expression Checks: Strengthen regular expression checks to ensure that they cannot be bypassed.
• Network Security: Implement network security measures such as firewalls and intrusion detection systems to monitor and block suspicious traffic.
• Patch Management: Ensure that all software dependencies are regularly updated and patched.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations within the European Union that use h2oai/h2o-3. Given the critical nature of the vulnerability, it could lead to data breaches, unauthorized access, and system downtime. This underscores the importance of timely patching and adherence to best practices in cybersecurity.

6. Technical Details for Security Professionals

• Vulnerability Type: Deserialization vulnerability.
• Exploitation Method: Bypassing regular expression checks using double URL encoding.
• Impact: Arbitrary file read and code execution.
• Affected Versions: h2oai/h2o-3 versions <= 3.46.0.8.
• Mitigation: Upgrade to a patched version, implement robust input validation, and strengthen network security measures.

References

• Huntr Bounty: Huntr Bounty
• GitHub Commit: GitHub Commit

Conclusion

The deserialization vulnerability in h2oai/h2o-3 versions <= 3.46.0.8 is critical and requires immediate attention. Organizations should prioritize updating to a patched version and implementing additional security measures to mitigate the risk. This vulnerability highlights the importance of continuous monitoring and prompt response to security threats in the European cybersecurity landscape.