Name: CVE-2016-4864: Use of Externally-Controlled Format String
Creator: Rapid7
Published: 2017-05-12T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2016-4864, CWE-134, CVSS 7.5, EPSS 0.01598

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 Details

CVSS 3.0 Base Score: 7.5
CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Freebsd	—	Upgrade h2o	Dec 10, 2025	Sep 14, 2016

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CVSS Details

Covered by Rapid7

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