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.
Conclusion & alert: CVE-2017-10868 is rated Moderate Risk (62.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.47%). Core evidence: EPSS rose +2.25% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 1.22% | 3.47% | +2.25% |
| 2 | 2025-03-30 | 1.69% | 1.22% | -0.47% |
| 3 | 2025-03-29 | — | 1.69% | — |
Full EPSS history (7 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
medium | CVE-2017-10868 medium priority: Debian including 1 source packages (h2o), 2 status rows across 2 suites (bookworm, bullseye): resolved 2. | https://security-tracker.debian.org/tracker/CVE-2017-10868 |
ubuntu
|
medium | CVE-2017-10868 medium priority: Ubuntu including 1 source packages (h2o), 5 status rows across 5 suites (artful, trusty, upstream, xenial, zesty): DNE 4, released 1. | https://ubuntu.com/security/CVE-2017-10868 |
| URL | Tags |
|---|---|
| https://github.com/h2o/h2o/issues/1459 | Third Party Advisory |
| https://jvn.jp/en/jp/JVN84182676/index.html | Third Party Advisory VDB Entry |