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USN-5186-1: Firefox vulnerabilities

9 December 2021

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

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Releases

Packages

  • firefox - Mozilla Open Source web browser

Details

Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information, conduct spoofing attacks, bypass CSP restrictions, or
execute arbitrary code. (CVE-2021-43536, CVE-2021-43537, CVE-2021-43538,
CVE-2021-43539, CVE-2021-43541, CVE-2021-43542, CVE-2021-43543,
CVE-2021-43545, CVE-2021-43546)

A security issue was discovered with the handling of WebExtension
permissions. If a user were tricked into installing a specially crafted
extension, an attacker could potentially exploit this to create and
install a service worker that wouldn't be uninstalled with the extension.
(CVE-2021-43540)

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 21.10
Ubuntu 21.04
Ubuntu 20.04
Ubuntu 18.04

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

Related notices

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