USN-4421-1: Thunderbird vulnerabilities

8 July 2020

Several security issues were fixed in Thunderbird.

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

Releases

Packages

  • thunderbird - Mozilla Open Source mail and newsgroup client

Details

Multiple security issues were discovered in Thunderbird. If a user were
tricked in to opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, or execute arbtirary code. (CVE-2020-12405,
CVE-2020-12406, CVE-2020-12410, CVE-2020-12417, CVE-2020-12418,
CVE-2020-12419, CVE-2020-12420)

It was discovered that Thunderbird would continue an unencrypted
connection when configured to use STARTTLS for IMAP if the server
responded with PREAUTH. A remote attacker could potentially exploit
this to perform a person-in-the-middle attack in order to obtain
sensitive information. (CVE-2020-12398)

It was discovered that NSS showed timing differences when performing DSA
signatures. An attacker could potentially exploit this to obtain private
keys using a timing attack. (CVE-2020-12399)

It was discovered that when performing add-on updates, certificate chains
not terminating with built-in roots were silently rejected. This could
result in add-ons becoming outdated. (CVE-2020-12421)

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 20.04
Ubuntu 19.10
Ubuntu 18.04
Ubuntu 16.04

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