A Netty security update has been released for Ubuntu Linux 18.04 LTS.

USN-4532-1: Netty vulnerabilities

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Ubuntu Security Notice USN-4532-1
September 22, 2020

netty-3.9 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in Netty.

Software Description:
- netty-3.9: Asynchronous event-driven network application framework

Details:

It was discovered that Netty incorrectly handled certain HTTP headers.
By sending an HTTP header with whitespace before the colon, a remote
attacker could possibly use this issue to perform an HTTP request
smuggling attack. (CVE-2019-16869)

It was discovered that Netty incorrectly handled certain HTTP headers.
By sending an HTTP header that lacks a colon, a remote attacker could
possibly use this issue to perform an HTTP request smuggling attack.
(CVE-2019-20444)

It was discovered that Netty incorrectly handled certain HTTP headers.
By sending a Content-Length header accompanied by a second
Content-Length header, or by a Transfer-Encoding header, a remote
attacker could possibly use this issue to perform an HTTP request
smuggling attack. (CVE-2019-20445)

Update instructions:

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

Ubuntu 18.04 LTS:
libnetty-3.9-java 3.9.9.Final-1+deb9u1build0.18.04.1

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

References:
  https://usn.ubuntu.com/4532-1
CVE-2019-16869, CVE-2019-20444, CVE-2019-20445

Package Information:

  https://launchpad.net/ubuntu/+source/netty-3.9/3.9.9.Final-1+deb9u1build0.18.04.1