Critical

H2O affected by a deserialization vulnerability

  • Disclosed: 22.09.2025
  • Updated: 11.10.2026 12:20

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 software

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PlatformPackageVulnerable versionsFixed in
Java / Kotlin (Maven) ai.h2o:h2o-core <= 3.46.0.7 no fix
Python (PyPI) h2o <= 3.46.0.7 no fix

References

CVSS score 9.8/10
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE)
CWE-502
Platform
Java / Kotlin (Maven), Python (PyPI)
Package
ai.h2o:h2o-core, h2o
Disclosed
22.09.2025
Updated
11.10.2026 12:20

Sources and licenses

OSV / GitHub Advisory Database - GHSA-5w3j-gwgh-4rfv - CC BY 4.0

OSV / GitHub Advisory Database - PYSEC-2026-349 - PyPA Advisory Database; CC BY 4.0

Vulnerability history: ai.h2o:h2o-core

All published vulnerabilities of this package (Java / Kotlin (Maven)), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (15) in the archive
Total entries
15
First → latest
11.2023 04.2026
Without a fix
13
Exploited in attacks
0

Severity breakdown

  • Critical 6
  • High 8
  • Medium 1

Disclosures per year

  1. 2023: 1
  2. 2024: 2
  3. 2025: 10
  4. 2026: 2
Severity:
  1. Critical · 9.1 CVE-2024-5986 <= 3.46.0.1 no fix
  2. H2O affected by a deserialization vulnerability this entry
    Critical · 9.8 CVE-2025-6544 <= 3.46.0.7 no fix
  3. High · 8.2 CVE-2024-8616 >= 3.10.4.1, <= 3.46.0 no fix
  4. High · 7.5 CVE-2024-8062 >= 3.2.0.1, <= 3.46.0 no fix
  5. High · 7.5 CVE-2024-7765 >= 3.32.1.2, <= 3.46.0.2 no fix
  6. High · 7.1 CVE-2024-6854 >= 3.32.1.1, <= 3.46.0 no fix
  7. High · 7.5 CVE-2024-10550 >= 3.30.0.7, <= 3.46.0.1 no fix
  8. High · 7.5 CVE-2024-10549 >= 3.30.0.7, <= 3.46.0.1 no fix
  9. Critical · 9.8 CVE-2024-10553 < 3.46.0.6 3.46.0.6
  10. Critical · 9.1 CVE-2024-45758 <= 3.46.0.7 no fix
  11. High · 7.5 CVE-2024-6960 <= 3.46.0.4 no fix
  12. Critical · 9.3 CVE-2023-6038 <= 3.40.0.4 no fix

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