A Firefox security update has been released for Ubuntu Linux 20.04 LTS, 19.10, 18.04 LTS, and 16.04 LTS.

USN-4353-1: Firefox vulnerabilities

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Ubuntu Security Notice USN-4353-1
May 07, 2020

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

- Ubuntu 20.04 LTS
- Ubuntu 19.10
- 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, bypass security
restrictions, spoof the URL bar, or execute arbitrary code.
(CVE-2020-6831, CVE-2020-12387, CVE-2020-12390, CVE-2020-12391,
CVE-2020-12394, CVE-2020-12395, CVE-2020-12396)

It was discovered that the Devtools’ ‘Copy as cURL’ feature did not
properly HTTP POST data of a request. If a user were tricked in to using
the ‘Copy as cURL’ feature to copy and paste a command with specially
crafted data in to a terminal, an attacker could potentially exploit this
to obtain sensitive information from local files.
(CVE-2020-12392)

Update instructions:

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

Ubuntu 20.04 LTS:
firefox 76.0+build2-0ubuntu0.20.04.1

Ubuntu 19.10:
firefox 76.0+build2-0ubuntu0.19.10.1

Ubuntu 18.04 LTS:
firefox 76.0+build2-0ubuntu0.18.04.1

Ubuntu 16.04 LTS:
firefox 76.0+build2-0ubuntu0.16.04.1

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

References:
https://usn.ubuntu.com/4353-1
CVE-2020-12387, CVE-2020-12390, CVE-2020-12391, CVE-2020-12392,
CVE-2020-12394, CVE-2020-12395, CVE-2020-12396, CVE-2020-6831

Package Information:
https://launchpad.net/ubuntu/+source/firefox/76.0+build2-0ubuntu0.20.04.1
https://launchpad.net/ubuntu/+source/firefox/76.0+build2-0ubuntu0.19.10.1
https://launchpad.net/ubuntu/+source/firefox/76.0+build2-0ubuntu0.18.04.1
https://launchpad.net/ubuntu/+source/firefox/76.0+build2-0ubuntu0.16.04.1