USN-4671-1: Firefox vulnerabilities

15 December 2020

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, bypass the CSS sanitizer, bypass security restrictions,
spoof the URL bar, or execute arbitrary code. (CVE-2020-16042,
CVE-2020-26971, CVE-2020-26972, CVE-2020-26793, CVE-2020-26974,
CVE-2020-26976, CVE-2020-26978, CVE-2020-26979,
CVE-2020-35113, CVE-2020-35114)

It was discovered that the proxy.onRequest API did not catch
view-source URLs. If a user were tricked in to installing an
extension with the proxy permission and opening View Source, an
attacker could potentially exploit this to obtain sensitive
information. (CVE-2020-35111)

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.

References

Related notices

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