AI and data stack advisories

Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

H2O-3GHSA-5w3j-gwgh-4rfv

H2O affected by a deserialization vulnerability

H2O-3

CVE-2025-6544 · Published Sep 22, 2025 · updated Oct 27, 2026

Critical9.8
No fix yet
GitHub advisory

A deserialization vulnerability exists in h2oai/h2o-3 versions <= 3.46.0.7, allowing attackers to read arbitrary system files and execute arbitrary code. The vulnerability arises from improper handling of JDBC connection parameters, which can be exploited by bypassing regular expression checks and using double URL encoding. This issue impacts all users of the affected versions.

Affected versions

PackageAffectedFixed in
h2o
PyPI
<= 3.46.0.7No fix yet
Details and references

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