A Tomcat security update has been released for Ubuntu Linux 16.04 LTS.

USN-4448-1: Tomcat vulnerabilities

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Ubuntu Security Notice USN-4448-1
August 04, 2020

tomcat8 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Tomcat.

Software Description:
- tomcat8: Servlet and JSP engine

Details:

It was discovered that Tomcat incorrectly validated the payload length in
a WebSocket frame. A remote attacker could possibly use this issue to cause
Tomcat to hang, resulting in a denial of service. (CVE-2020-13935)

It was discovered that Tomcat incorrectly handled HTTP header parsing. In
certain environments where Tomcat is located behind a reverse proxy, a
remote attacker could possibly use this issue to perform HTTP Reqest
Smuggling. (CVE-2020-1935)

It was discovered that Tomcat incorrectly handled certain uncommon
PersistenceManager with FileStore configurations. A remote attacker could
possibly use this issue to execute arbitrary code. (CVE-2020-9484)

Update instructions:

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

Ubuntu 16.04 LTS:
libtomcat8-java 8.0.32-1ubuntu1.13
tomcat8 8.0.32-1ubuntu1.13

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

References:
  https://usn.ubuntu.com/4448-1
CVE-2020-13935, CVE-2020-1935, CVE-2020-9484

Package Information:
  https://launchpad.net/ubuntu/+source/tomcat8/8.0.32-1ubuntu1.13