CVE-2025-6544: Deserialization Vulnerability in h2oai/h2o-3

Published Sep 21, 2025
·
Updated

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.

Other sources

A deserialization vulnerability exists in h2oai/h2o-3 versions <= 3.46.0.8, 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.

MITRE

Affected Software

4 affected components
h2oai h2o-3<3.46.0.8
pip/h2o<=3.46.0.7
maven/ai.h2o:h2o-core<=3.46.0.7
h2o h2o>=3.0.0.2<=3.46.0.8

Event History

Sep 21, 2025
CVE Published
via MITRE·09:00 AM
Data Sourced
via MITRE·09:00 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·09:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
Sep 22, 2025
Advisory Published
via GitHub·06:30 PM
Data Sourced
via GitHub·06:30 PM
DescriptionSeverityWeaknessAffected Software
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2025-6544?

CVE-2025-6544 has a high severity rating due to its potential for remote code execution and disclosure of sensitive system files.

2

How do I fix CVE-2025-6544?

To fix CVE-2025-6544, upgrade to h2oai/h2o-3 version 3.46.0.9 or later where the deserialization vulnerability has been addressed.

3

What vulnerabilities does CVE-2025-6544 introduce?

CVE-2025-6544 introduces vulnerabilities that allow attackers to read arbitrary system files and execute arbitrary code.

4

Which versions of h2o-3 are affected by CVE-2025-6544?

CVE-2025-6544 affects all h2oai/h2o-3 versions up to and including 3.46.0.8.

5

What causes the CVE-2025-6544 vulnerability?

The CVE-2025-6544 vulnerability is caused by improper handling of JDBC connection parameters leading to deserialization issues.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203