USN-4647-1: Thunderbird vulnerabilities

25 November 2020

Several security issues were fixed in Thunderbird.



  • thunderbird - Mozilla Open Source mail and newsgroup client


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 across origins, bypass security restrictions,
conduct phishing attacks, conduct cross-site scripting (XSS) attacks,
bypass Content Security Policy (CSP) restrictions, conduct DNS rebinding
attacks, or execute arbitrary code.

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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