CVE-2020-11993

Publication date 7 August 2020

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Apache HTTP Server versions 2.4.20 to 2.4.43 When trace/debug was enabled for the HTTP/2 module and on certain traffic edge patterns, logging statements were made on the wrong connection, causing concurrent use of memory pools. Configuring the LogLevel of mod_http2 above "info" will mitigate this vulnerability for unpatched servers.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
apache2	20.04 LTS focal	Fixed 2.4.41-4ubuntu3.1
	18.04 LTS bionic	Fixed 2.4.29-1ubuntu4.14
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Patch details

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

Package	Patch details
apache2	Upstream: https://svn.apache.org/r1879642 Upstream: 63a0a87

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-4458-1
Apache HTTP Server vulnerabilities
13 August 2020