USN-4701-1: Thunderbird vulnerabilities

20 January 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 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, bypass the CSS sanitizer, or execute
arbitrary code. (CVE-2020-16042, CVE-2020-16044, CVE-2020-26971,
CVE-2020-26973, CVE-2020-26974, CVE-2020-26978, CVE-2020-35113)

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)

A stack overflow was discovered due to incorrect parsing of SMTP server
response codes. An attacker could potentially exploit this to execute
arbitrary code. (CVE-2020-26970)

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

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

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