h2oai h2o-3 up to 3.46.7 JDBC Connection deserialization

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in h2oai h2o-3 up to 3.46.7. Affected is an unknown function of the component JDBC Connection Handler. This manipulation causes deserialization. The identification of this vulnerability is CVE-2025-6544. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in h2oai h2o-3 up to 3.46.7. It has been declared as critical. Affected by this vulnerability is some unknown functionality of the component JDBC Connection Handler. The manipulation with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at huntr.com. This vulnerability is known as CVE-2025-6544 since 06/23/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 3.46.8 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-30380). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (@huntr_ai): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: h2o-3 3.46.8

Timelineinfo

06/23/2025 CVE reserved
09/21/2025 +90 days Advisory disclosed
09/21/2025 +0 days VulDB entry created
09/21/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: huntr.com
Status: Confirmed

CVE: CVE-2025-6544 (🔒)
GCVE (CVE): GCVE-0-2025-6544
GCVE (VulDB): GCVE-100-325159
EUVD: 🔒

Entryinfo

Created: 09/21/2025 11:39
Updated: 09/21/2025 13:20
Changes: 09/21/2025 11:39 (63), 09/21/2025 13:20 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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