A Firefox security update has been released for Ubuntu Linux 20.04 LTS, 18.04 LTS, and 16.04 LTS.

USN-4443-1: Firefox vulnerabilities

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Ubuntu Security Notice USN-4443-1
July 29, 2020

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

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Firefox could be made to crash or run programs as your login if it
opened a malicious website.

Software Description:
- firefox: Mozilla Open Source web browser

Details:

Multiple security issues were discovered in Firefox. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information, bypass iframe sandbox restrictions, confuse the user, or
execute arbitrary code. (CVE-2020-6463, CVE-2020-6514, CVE-2020-15652,
CVE-2020-15653, CVE-2020-15654, CVE-2020-15656, CVE-2020-15658,
CVE-2020-15659)

It was discovered that redirected HTTP requests which are observed or
modified through a web extension could bypass existing CORS checks. If a
user were tricked in to installing a specially crafted extension, an
attacker could potentially exploit this to obtain sensitive information
across origins. (CVE-2020-15655)

Update instructions:

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

Ubuntu 20.04 LTS:
firefox 79.0+build1-0ubuntu0.20.04.1

Ubuntu 18.04 LTS:
firefox 79.0+build1-0ubuntu0.18.04.1

Ubuntu 16.04 LTS:
firefox 79.0+build1-0ubuntu0.16.04.2

After a standard system update you need to restart Firefox to make
all the necessary changes.

References:
  https://usn.ubuntu.com/4443-1
CVE-2020-15652, CVE-2020-15653, CVE-2020-15654, CVE-2020-15655,
CVE-2020-15656, CVE-2020-15658, CVE-2020-15659, CVE-2020-6463,
CVE-2020-6514

Package Information:
  https://launchpad.net/ubuntu/+source/firefox/79.0+build1-0ubuntu0.20.04.1
  https://launchpad.net/ubuntu/+source/firefox/79.0+build1-0ubuntu0.18.04.1
  https://launchpad.net/ubuntu/+source/firefox/79.0+build1-0ubuntu0.16.04.2