CVE-2017-9789

Publication date 13 July 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

When under stress, closing many connections, the HTTP/2 handling code in Apache httpd 2.4.26 would sometimes access memory after it has been freed, resulting in potentially erratic behaviour.

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

Notes

sbeattie

HTTP/2 support has not been enabled in Ubuntu builds of apache

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · High

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	7.5 · High
Exploitability score	-
Impact score	-

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H