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USN-4995-1: Thunderbird vulnerabilities

22 June 2021

Several security issues were fixed in Thunderbird.

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Releases

Packages

  • 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,
obtain sensitive information, spoof the UI, bypass security restrictions,
or execute arbitrary code. (CVE-2021-23961, CVE-2021-23981,
CVE-2021-23982, CVE-2021-23987, CVE-2021-23994, CVE-2021-23998,
CVE-2021-23999, CVE-2021-29945, CVE-2021-29946, CVE-2021-29967)

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 spoof a website and trick the user into providing
credentials. (CVE-2021-23984)

Multiple security issues were discovered in Thunderbird's OpenPGP
integration. If a user were tricked into importing a specially crafted
key in some circumstances, an attacker could potentially exploit this
to cause a denial of service (inability to send encrypted email) or
confuse the user. (CVE-2021-23991, CVE-2021-23992, CVE-2021-23993)

A use-after-free was discovered when Responsive Design Mode was
enabled. If a user were tricked into opening a specially crafted
website with Responsive Design Mode enabled, an attacker could
potentially exploit this to cause a denial of service, or execute
arbitrary code. (CVE-2021-23995)

It was discovered that Thunderbird mishandled ftp URLs with encoded
newline characters. If a user were tricked into clicking on a specially
crafted link, an attacker could potentially exploit this to send arbitrary
FTP commands. (CVE-2021-24002)

It was discovered that Thunderbird wrote signatures to disk and read them
back during verification. A local attacker could potentially exploit this
to replace the data with another signature file. (CVE-2021-29948)

It was discovered that Thunderbird might load an alternative OTR
library. If a user were tricked into copying a specially crafted
library to one of Thunderbird's search paths, an attacker could
potentially exploit this to execute arbitrary code. (CVE-2021-29949)

It was discovered that secret keys imported into Thunderbird were
stored unencrypted. A local attacker could potentially exploit this to
obtain private keys. (CVE-2021-29956)

It was discovered that Thunderbird did not indicate when an inline signed
or encrypted message contained additional unprotected parts.
(CVE-2021-29957)

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 21.04
Ubuntu 20.10
Ubuntu 20.04

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

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