USN-4717-2: Firefox regression

8 February 2021

USN-4717-1 introduced a regression in Firefox.

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Releases

Packages

  • firefox - Mozilla Open Source web browser

Details

USN-4717-1 fixed vulnerabilities in Firefox. The update caused a
startup hang in some circumstances. This update fixes the problem.

We apologize for the inconvenience.

Original advisory 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, conduct clickjacking attacks, or execute arbitrary code.

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 20.10
Ubuntu 20.04
Ubuntu 18.04
Ubuntu 16.04

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