CVE-2016-8740: Apache HTTP Server

High severity, CVSS 7.5. EPSS: 79.1% chance of exploitation in the next 30 days.

The mod_http2 module in the Apache HTTP Server 2.4.17 through 2.4.23, when the Protocols configuration includes h2 or h2c, does not restrict request-header length, which allows remote attackers to cause a denial of service (memory consumption) via crafted CONTINUATION frames in an HTTP/2 request.

Affected products

• Apache HTTP Server: version 2.4.17 only; version 2.4.18 only; version 2.4.19 only; version 2.4.20 only; version 2.4.21 only; version 2.4.22 only; …

Published 2016-12-05. Last modified 2026-06-17.