High

H2O Vulnerable to Denial of Service (DoS) via `HEAD` Request

  • Disclosed: 20.03.2025
  • Updated: 11.10.2026 13:18

A vulnerability in the typeahead endpoint of h2oai/h2o-3 version 3.46.0 allows for a denial of service. The endpoint performs a HEAD request to verify the existence of a specified resource without setting a timeout. An attacker can exploit this by sending multiple requests to an attacker-controlled server that hangs, causing the application to block and become unresponsive to other requests.

Affected software

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PlatformPackageVulnerable versionsFixed in
Java / Kotlin (Maven) ai.h2o:h2o-core >= 3.2.0.1, <= 3.46.0 no fix
Python (PyPI) h2o >= 3.2.0.1, <= 3.46.0 no fix

References

CVSS score 7.5/10
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-1088
Platform
Java / Kotlin (Maven), Python (PyPI)
Package
ai.h2o:h2o-core, h2o
Disclosed
20.03.2025
Updated
11.10.2026 13:18

Sources and licenses

OSV / GitHub Advisory Database - GHSA-5c8j-g96x-cj78 - CC BY 4.0

OSV / GitHub Advisory Database - PYSEC-2026-1438 - PyPA Advisory Database; CC BY 4.0

Vulnerability history: h2o

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

All (17) in the archive
Total entries
17
First → latest
12.2023 04.2026
Without a fix
14
Exploited in attacks
0

Severity breakdown

  • Critical 6
  • High 9
  • Medium 2

Disclosures per year

  1. 2023: 1
  2. 2024: 3
  3. 2025: 11
  4. 2026: 2
Severity:
  1. Critical · 9.1 CVE-2024-5986 <= 3.46.0.1 no fix
  2. 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. H2O Vulnerable to Denial of Service (DoS) via `HEAD` Request this entry
    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-2024-10572 >= 3.34.0.1, <= 3.46.0.1 no fix
  8. High · 7.5 CVE-2024-10550 >= 3.30.0.7, <= 3.46.0.1 no fix
  9. High · 7.5 CVE-2024-10549 >= 3.30.0.7, <= 3.46.0.1 no fix
  10. Critical · 9.8 CVE-2024-10553 < 3.46.0.6 3.46.0.6
  11. Critical · 9.1 CVE-2024-45758 <= 3.46.0.7 no fix
  12. High · 7.5 CVE-2024-5979 <= 3.46.0 no fix
  13. Critical · 9.3 CVE-2023-6569 < 3.46.0.1 3.46.0.1

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