CVE-2018-17189

Publication date 30 January 2019

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

In Apache HTTP server versions 2.4.37 and prior, by sending request bodies in a slow loris way to plain resources, the h2 stream for that request unnecessarily occupied a server thread cleaning up that incoming data. This affects only HTTP/2 (mod_http2) connections.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
apache2	18.10 cosmic	Fixed 2.4.34-1ubuntu2.1
	18.04 LTS bionic	Fixed 2.4.29-1ubuntu4.6
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Notes

leosilva

issue was introduced in 2.4.17

mdeslaur

http2 is disabled in xenial

Patch details

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

Package	Patch details
apache2	Upstream: bea40bf

Severity score breakdown

Parameter	Value
Base score	5.3 · Medium
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	Low
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

Related Ubuntu Security Notices (USN)

USN-3937-1
Apache HTTP Server vulnerabilities
4 April 2019