What is CVE-2017-10868?

CVE-2017-10868 is a high-severity vulnerability in Dena H2o, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2017-12-22.

How severe is CVE-2017-10868?

High severity. CVSS v3 base score is 7.5 out of 10.

Improper input validation in Dena H2o

CVE-2017-10868

H2O version 2.2.2 and earlier allows remote attackers to cause a denial of service in the server via specially crafted HTTP/1 header.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2017-12-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.035 (88.8th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 88.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.035 · newest: 0.035 · change: 0.000

Affected products

Dena H2o
Kazuho Oku H2o — versions version 2.2.2 and earlier

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

github.com/h2o/h2o/issues/1459 (Third Party Advisory)
jvn.jp/en/jp/JVN84182676/index.html (VDB Entry, Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2017-10868?: CVE-2017-10868 is a high-severity vulnerability in Dena H2o, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2017-12-22.
How severe is CVE-2017-10868?: High severity. CVSS v3 base score is 7.5 out of 10.