USN-4202-1: Thunderbird vulnerabilities

26 November 2019

Several security issues were fixed in Thunderbird.

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Releases

Packages

  • thunderbird - Mozilla Open Source mail and newsgroup client

Details

It was discovered that a specially crafted S/MIME message with an inner
encryption layer could be displayed as having a valid signature in some
circumstances, even if the signer had no access to the encrypted message.
An attacker could potentially exploit this to spoof the message author.
(CVE-2019-11755)

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,
bypass security restrictions, bypass same-origin restrictions, conduct
cross-site scripting (XSS) attacks, or execute arbitrary code.
(CVE-2019-11757, CVE-2019-11758, CVE-2019-11759, CVE-2019-11760,
CVE-2019-11761, CVE-2019-11762, CVE-2019-11763, CVE-2019-11764)

A heap overflow was discovered in the expat library in Thunderbird. If a
user were tricked in to opening a specially crafted message, an attacker
could potentially exploit this to cause a denial of service, or execute
arbitrary code. (CVE-2019-15903)

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 19.10
Ubuntu 18.04

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