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

USN-4561-1: Rack vulnerabilities

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Ubuntu Security Notice USN-4561-1
September 30, 2020

ruby-rack vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS

Summary:

Rack could be made to expose sensitive information over the network.

Software Description:
- ruby-rack: modular Ruby webserver interface

Details:

It was discovered that Rack incorrectly handled certain paths. An attacker
could possibly use this issue to obtain sensitive information.
(CVE-2020-8161)

It was discovered that Rack incorrectly validated cookies. An attacker
could possibly use this issue to forge a secure cookie. (CVE-2020-8184)

Update instructions:

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

Ubuntu 18.04 LTS:
ruby-rack 1.6.4-4ubuntu0.2

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

References:
  https://usn.ubuntu.com/4561-1
CVE-2020-8161, CVE-2020-8184

Package Information:
  https://launchpad.net/ubuntu/+source/ruby-rack/1.6.4-4ubuntu0.2