Is CVE-2016-4864 actively exploited?

CVE-2016-4864 has no public evidence of in-the-wild exploitation as of 2025-04-20.

What is the CVSS score for CVE-2016-4864?

CVE-2016-4864 has a CVSS score of 7.5 (HIGH severity). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

How do I patch CVE-2016-4864?

Patch guidance is available from dena security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2016-4864.

Which products are affected by CVE-2016-4864?

3 products: dena h2o, dena h2o, dena h2o.

Fix CVE-2016-4864 - HIGH dena h2o

Description

H2O versions 2.0.3 and earlier and 2.1.0-beta2 and earlier allows remote attackers to cause a denial-of-service (DoS) via format string specifiers in a template file via fastcgi, mruby, proxy, redirect or reproxy.

CVSS Metrics

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector: network
Complexity: low
Privileges: none
User Action: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high
Weaknesses: CWE-134

Metadata

Primary Vendor: DENA
Published: 5/12/2017
Last Modified: 4/20/2025
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

dena : h2odena : h2odena : h2o

Remediation Guidance

Executive Summary

Cite this page

CVE-2016-4864. CVEDatabase.com. Retrieved 1 May 2026. https://cvedatabase.com/cve/CVE-2016-4864

View on NIST NVD

CVE-2016-4864 vulnerability