by Kastro
Paper/Archive/CVE-2025-6544

CVE-2025-6544

h2oai h2oai/h2o-3 — Deserialization Vulnerability in h2oai/h2o-3

EPSS 0.9%public exploitCVSS 9.8
critical.is priorityof 100
52
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 60.3.603 × 2012.1Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
h2oai/h2o-3unspecified – < 3.46.83.46.8CNA

Scores by source

@huntr_ai (CNA)9.8CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploithuntr.com/bounties/53f35a0f-d644-4f82-93aa-89fe7e0aed40refgithub.com/h2oai/h2o-3/commit/0298ee348f5c73673b7b542158081e79605f5f25