CVE-2016-8740

Publication date 5 December 2016

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
apache2	17.04 zesty	Not affected
	16.10 yakkety	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
	12.04 LTS precise	Not affected

Notes

mdeslaur

mod_http2 is not built in Ubuntu because it is considered experimental.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
apache2	Upstream: 29c63b7 Upstream: https://svn.apache.org/viewvc?view=revision&revision=1772579

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H