USN-5090-3: Apache HTTP Server regression

Publication date

28 September 2021

Overview

USN-5090-1 introduced a regression in Apache HTTP Server.


Packages

Details

USN-5090-1 fixed vulnerabilities in Apache HTTP Server. One of the upstream
fixes introduced a regression in UDS URIs. This update fixes the problem.

Original advisory details:

James Kettle discovered that the Apache HTTP Server HTTP/2 module
incorrectly handled certain crafted methods. A remote attacker could
possibly use this issue to perform request splitting or cache poisoning
attacks. (CVE-2021-33193)

It was discovered that the Apache HTTP Server incorrectly handled certain
malformed requests. A remote attacker could possibly use this issue to
cause the server to crash, resulting in a denial of service.
(CVE-2021-34798)

Li Zhi Xin discovered that the Apache mod_proxy_uwsgi module incorrectly
handled certain request uri-paths. A remote attacker could possibly use
this issue to cause the server to crash, resulting in a denial of...

USN-5090-1 fixed vulnerabilities in Apache HTTP Server. One of the upstream
fixes introduced a regression in UDS URIs. This update fixes the problem.

Original advisory details:

James Kettle discovered that the Apache HTTP Server HTTP/2 module
incorrectly handled certain crafted methods. A remote attacker could
possibly use this issue to perform request splitting or cache poisoning
attacks. (CVE-2021-33193)

It was discovered that the Apache HTTP Server incorrectly handled certain
malformed requests. A remote attacker could possibly use this issue to
cause the server to crash, resulting in a denial of service.
(CVE-2021-34798)

Li Zhi Xin discovered that the Apache mod_proxy_uwsgi module incorrectly
handled certain request uri-paths. A remote attacker could possibly use
this issue to cause the server to crash, resulting in a denial of service.
This issue only affected Ubuntu 20.04 LTS and Ubuntu 21.04.
(CVE-2021-36160)

It was discovered that the Apache HTTP Server incorrectly handled escaping
quotes. If the server was configured with third-party modules, a remote
attacker could use this issue to cause the server to crash, resulting in a
denial of service, or possibly execute arbitrary code. (CVE-2021-39275)

It was discovered that the Apache mod_proxy module incorrectly handled
certain request uri-paths. A remote attacker could possibly use this issue
to cause the server to forward requests to arbitrary origin servers.
(CVE-2021-40438)


Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
21.04 hirsute apache2 –  2.4.46-4ubuntu1.3
apache2-bin –  2.4.46-4ubuntu1.3
20.04 focal apache2 –  2.4.41-4ubuntu3.6
apache2-bin –  2.4.41-4ubuntu3.6
18.04 bionic apache2 –  2.4.29-1ubuntu4.18
apache2-bin –  2.4.29-1ubuntu4.18

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