USN-4893-1: Firefox vulnerabilities

25 March 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, 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)

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.

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