AI and data stack advisories

Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

H2O-3PYSEC-2026-2180

H2O-3: remote code execution

H2O-3

CVE-2026-3960 · Published Apr 23, 2026 · updated Jul 13, 2026

Critical9.8
Fix: upgrade to 3.46.0.10 or later
Source advisory

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 versions

PackageAffectedFixed in
h2o
PyPI
< 3.46.0.103.46.0.10
Details and references
CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity from
the CVSS score
Also known as
CVE-2026-3960, GHSA-qmcv-hh7c-3m56

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