An Apache HTTP Server security update has been released for Ubuntu 14.04 ESM and 16.04 ESM.

USN-5333-2: Apache HTTP Server vulnerabilities

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Ubuntu Security Notice USN-5333-2
March 17, 2022

apache2 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

Several security issues were fixed in Apache HTTP Server.

Software Description:
- apache2: Apache HTTP server

Details:

USN-5333-1 fixed several vulnerabilities in Apache. This update provides
the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.

Original advisory details:

Chamal De Silva discovered that the Apache HTTP Server mod_lua module
incorrectly handled certain crafted request bodies. A remote attacker could
possibly use this issue to cause the server to crash, resulting in a denial
of service. (CVE-2022-22719)

James Kettle discovered that the Apache HTTP Server incorrectly closed
inbound connection when certain errors are encountered. A remote attacker
could possibly use this issue to perform an HTTP Request Smuggling attack.
(CVE-2022-22720)

It was discovered that the Apache HTTP Server incorrectly handled large
LimitXMLRequestBody settings on certain platforms. In certain
configurations, 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-2022-22721)

Ronald Crane discovered that the Apache HTTP Server mod_sed module
incorrectly handled memory. 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-2022-23943)

Update instructions:

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

Ubuntu 16.04 ESM:
apache2 2.4.18-2ubuntu3.17+esm5
apache2-bin 2.4.18-2ubuntu3.17+esm5

Ubuntu 14.04 ESM:
apache2 2.4.7-1ubuntu4.22+esm4
apache2-bin 2.4.7-1ubuntu4.22+esm4

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

References:
  https://ubuntu.com/security/notices/USN-5333-2
  https://ubuntu.com/security/notices/USN-5333-1
CVE-2022-22719, CVE-2022-22720, CVE-2022-22721, CVE-2022-23943