A Thunderbird security update has been released for Ubuntu Linux 18.04 LTS, 20.04 LTS, and 21.10.

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Ubuntu Security Notice USN-5345-1
March 23, 2022

thunderbird vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 21.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in Thunderbird.

Software Description:
- thunderbird: Mozilla Open Source mail and newsgroup client

Details:

Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service,
bypass security restrictions, obtain sensitive information, cause
undefined behaviour, spoof the browser UI, or execute arbitrary code.
(CVE-2022-22759, CVE-2022-22760, CVE-2022-22761, CVE-2022-22763,
CVE-2022-22764, CVE-2022-26381, CVE-2022-26383, CVE-2022-26384)

It was discovered that extensions of a particular type could auto-update
themselves and bypass the prompt that requests permissions. If a user
were tricked into installing a specially crafted extension, an attacker
could potentially exploit this to bypass security restrictions.
(CVE-2022-22754)

It was discovered that dragging and dropping an image into a folder could
result in it being marked as executable. If a user were tricked into
dragging and dropping a specially crafted image, an attacker could
potentially exploit this to execute arbitrary code. (CVE-2022-22756)

It was discovered that files downloaded to /tmp were accessible to other
users. A local attacker could exploit this to obtain sensitive
information. (CVE-2022-26386)

A TOCTOU bug was discovered when verifying addon signatures during
install. A local attacker could potentially exploit this to trick a
user into installing an addon with an invalid signature.
(CVE-2022-26387)

An out-of-bounds write by one byte was discovered when processing
messages in some circumstances. If a user were tricked into opening a
specially crafted message, an attacker could potentially exploit this
to cause a denial of service. (CVE-2022-0566)

Update instructions:

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

Ubuntu 21.10:
thunderbird 1:91.7.0+build2-0ubuntu0.21.10.1

Ubuntu 20.04 LTS:
thunderbird 1:91.7.0+build2-0ubuntu0.20.04.1

Ubuntu 18.04 LTS:
thunderbird 1:91.7.0+build2-0ubuntu0.18.04.1

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

References:
  https://ubuntu.com/security/notices/USN-5345-1
CVE-2022-0566, CVE-2022-22754, CVE-2022-22756, CVE-2022-22759,
CVE-2022-22760, CVE-2022-22761, CVE-2022-22763, CVE-2022-22764,
CVE-2022-26381, CVE-2022-26383, CVE-2022-26384, CVE-2022-26386,
CVE-2022-26387

Package Information:
  https://launchpad.net/ubuntu/+source/thunderbird/1:91.7.0+build2-0ubuntu0.21.10.1
  https://launchpad.net/ubuntu/+source/thunderbird/1:91.7.0+build2-0ubuntu0.20.04.1
  https://launchpad.net/ubuntu/+source/thunderbird/1:91.7.0+build2-0ubuntu0.18.04.1