6.5

CVE-2024-6863: Encryption of Arbitrary Files with Attacker-Controlled Key in h2oai/h2o-3

Analyzed
AliasesGHSA-m37h-8r48-2cxjPYSEC-2026-1442
Published 20-03-2025Last modified 15-10-2025

Vulnerability summary

CVE-2024-6863 is a medium (CVSS 6.5) Exposed Dangerous Method or Function vulnerability in h2o. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 29.4% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Routine

Not severe (CVSS 6.5, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.0 (CVE.org)
EPSS score
0.36%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1reference

Timeline

  1. 20-03-2025
    PublishedVulnerability first disclosed.
  2. 15-10-2025
    Last modifiedVulnerability information updated.

Description

In h2oai/h2o-3 version 3.46.0, an endpoint exposing a custom EncryptionTool allows an attacker to encrypt any files on the target server with a key of their choosing. The chosen key can also be overwritten, resulting in ransomware-like behavior. This vulnerability makes it possible for an attacker to encrypt arbitrary files with keys of their choice, making it exceedingly difficult for the target to recover the keys needed for decryption.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

29%

Versus all other CVEs

30-day change

Increase +0.01 pp

From 0.35% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (huntr.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ai.h2o1 product
  • h2o-core≥ 3.32.1.2, ≤ 3.46.0
H2o1 product
H2oai1 product
PyPI1 product
  • h2o≥ 3.32.1.2, ≤ 3.46.0

4 vendors · 4 products

References

6 links