CVE-2025-6544
CVSS v3
9.8
CRITICAL
EPSS Score
0.9 %
exploit probability, as of 2026-10-19
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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Affected and fixed versions
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Packages
- ai.h2o:h2o-coreMavenall versions · no fixed version listed
- h2oPyPIall versions · no fixed version listed
Description
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.
Technical details
- Published
- 2025-09-21
Frequently asked questions
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.