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

USN-4569-1: Yaws vulnerabilities

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Ubuntu Security Notice USN-4569-1
October 05, 2020

yaws 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 Yaws.

Software Description:
- yaws: High performance HTTP 1.1 webserver written in Erlang

Details:

It was discovered that Yaws did not properly sanitize XML input. A remote
attacker could use this vulnerability to execute an XML External Entity
(XXE) injection attack. (CVE-2020-24379)

It was discovered that Yaws mishandled certain input when running CGI
scripts. A remote attacker could use this vulnerability to execute
arbitrary commands. (CVE-2020-24916)

Update instructions:

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

Ubuntu 18.04 LTS:
erlang-yapp 2.0.4+dfsg-2ubuntu0.1
erlang-yaws 2.0.4+dfsg-2ubuntu0.1
yaws 2.0.4+dfsg-2ubuntu0.1
yaws-mail 2.0.4+dfsg-2ubuntu0.1

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

References:
  https://usn.ubuntu.com/4569-1
CVE-2020-24379, CVE-2020-24916

Package Information:
  https://launchpad.net/ubuntu/+source/yaws/2.0.4+dfsg-2ubuntu0.1