USN-4893-1: Firefox vulnerabilities

Publication date

25 March 2021

Overview

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


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, or execute arbitrary code. (CVE-2021-23981, CVE-2021-23982,
CVE-2021-23983, CVE-2021-23987, CVE-2021-23988)

It was discovered that extensions could open popup windows with control
of the window title in some circumstances. If a user were tricked into
installing a specially crafted extension, an attacker could potentially
exploit this to spook a website and trick the user into providing
credentials. (CVE-2021-23984)

It was discovered that the DevTools remote debugging feature could...

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, or execute arbitrary code. (CVE-2021-23981, CVE-2021-23982,
CVE-2021-23983, CVE-2021-23987, CVE-2021-23988)

It was discovered that extensions could open popup windows with control
of the window title in some circumstances. If a user were tricked into
installing a specially crafted extension, an attacker could potentially
exploit this to spook a website and trick the user into providing
credentials. (CVE-2021-23984)

It was discovered that the DevTools remote debugging feature could be
enabled without an indication to the user. If a local attacker could
modify the browser configuration, a remote attacker could potentially
exploit this to obtain sensitive information. (CVE-2021-23985)

It was discovered that extensions could read the response of cross
origin requests in some circumstances. If a user were tricked into
installing a specially crafted extension, an attacker could potentially
exploit this to obtain sensitive information. (CVE-2021-23986)


Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
20.10 groovy firefox –  87.0+build3-0ubuntu0.20.10.1
20.04 focal firefox –  87.0+build3-0ubuntu0.20.04.2
18.04 bionic firefox –  87.0+build3-0ubuntu0.18.04.2
16.04 xenial firefox –  87.0+build3-0ubuntu0.16.04.2

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