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USN-4383-1: Firefox vulnerabilities

4 June 2020

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

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  • firefox - Mozilla Open Source web browser


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, spoof the
addressbar, or execute arbitrary code. (CVE-2020-12405, CVE-2020-12406,
CVE-2020-12407, CVE-2020-12408, CVE-2020-12409, CVE-2020-12410,

It was discovered that NSS showed timing differences when performing DSA
signatures. An attacker could potentially exploit this to obtain private
keys using a timing attack. (CVE-2020-12399)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 20.04
Ubuntu 19.10
Ubuntu 18.04
Ubuntu 16.04

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

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