What’s Vulnerable › Vulnerabilities

CVE-2025-5662: Deserialization Vulnerability in h2oai/h2o-3

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-09-02 · updated 2026-06-17
• Weakness: CWE-502

Description

A deserialization vulnerability exists in the H2O-3 REST API (POST /99/ImportSQLTable) that affects all versions up to 3.46.0.7. This vulnerability allows remote code execution (RCE) due to improper validation of JDBC connection parameters when using a Key-Value format. The vulnerability is present in the MySQL JDBC Driver version 8.0.19 and JDK version 8u112. The issue is resolved in version 3.46.0.8.

Affected products

• h2oai/h2o-3: before 3.46.0.8 — fixed in 3.46.0.8

How to fix

Upgrade to a fixed version: h2oai/h2o-3 3.46.0.8. Check the vendor advisory for mitigations.

References

• https://github.com/h2oai/h2o-3/commit/f714edd6b8429c7a7211b779b6ec108a95b7382d
• https://huntr.com/bounties/057a743b-b2ec-4312-8262-ce0ff8bc161c

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