CVE-2026-3960
9.8 · CRITICALOverview
CVE-2026-3960 is a critical-severity vulnerability affecting h2o h2o. It was published on April 23, 2026 and has a CVSS 3.1 base score of 9.8 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
A critical remote code execution vulnerability exists in the unauthenticated REST API endpoint /99/ImportSQLTable in H2O-3 version 3.46.0.9 and prior. The vulnerability arises due to insufficient security controls in the parameter blacklist mechanism, which only targets MySQL JDBC driver-specific dangerous parameters. An attacker can bypass these controls by switching the JDBC URL protocol to jdbc:postgresql: and exploiting PostgreSQL JDBC driver-specific parameters such as socketFactory and socketFactoryArg. This allows unauthenticated attackers to execute arbitrary code on the H2O-3 server with the privileges of the H2O-3 process. The issue is resolved in version 3.46.0.10.
Remediation
Check the references section for vendor advisories and patches from h2o. Update h2o to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| h2o | h2o | >= 0, < 3.46.0.10 | Affected |
Frequently Asked Questions
What is CVE-2026-3960?
CVE-2026-3960 is a critical-severity vulnerability affecting h2o h2o. It was published on April 23, 2026 and has a CVSS 3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2026-3960?
This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-3960?
Check the references section for vendor advisories and patches from h2o. Update h2o to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-3960?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-3960 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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