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.
Affected products
h2o: h2o
References2
- github.com/h2oai/h2o-3/commit/b9ae2d3c5220db2dc53753357a783e590… Patch
- huntr.com/bounties/6954fe04-b905-453f-8c53-205ac8377e0d ExploitThird Party Advisory
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 61 · as of 13 November 2026
- CWE
- CWE-94
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