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USN-4373-1: Thunderbird vulnerabilities

26 May 2020

Several security issues were fixed in Thunderbird.

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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.

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  • 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,
or execute arbitrary code. (CVE-2020-6831, CVE-2020-12387, CVE-2020-12395)

It was discovered that the Devtools’ ‘Copy as cURL’ feature did not
properly escape the HTTP POST data of a request. If a user were tricked
in to using the ‘Copy as cURL’ feature to copy and paste a command with
specially crafted data in to a terminal, an attacker could potentially
exploit this to obtain sensitive information from local files.

It was discovered that Thunderbird did not correctly handle Unicode
whitespace characters within the From email header. An attacker could
potentially exploit this to spoof the sender email address that
Thunderbird displays. (CVE-2020-12397)

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 20.04
Ubuntu 19.10
Ubuntu 18.04
Ubuntu 16.04

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

Related notices

  • USN-4353-1: firefox-locale-lt, firefox-locale-bs, firefox-locale-et, firefox-dev, firefox-locale-ga, firefox-locale-ro, firefox-locale-gl, firefox-locale-te, firefox-mozsymbols, firefox-locale-tr, firefox-locale-ast, firefox-locale-ca, firefox-locale-gd, firefox-locale-af, firefox-locale-nl, firefox, firefox-locale-kk, firefox-locale-el, firefox-locale-sl, firefox-locale-ka, firefox-locale-fy, firefox-locale-fr, firefox-locale-ta, firefox-locale-kn, firefox-locale-be, firefox-locale-sv, firefox-locale-hsb, firefox-locale-fi, firefox-locale-hi, firefox-locale-cak, firefox-locale-hr, firefox-locale-my, firefox-locale-az, firefox-locale-hy, firefox-locale-nn, firefox-locale-mr, firefox-locale-ru, firefox-locale-xh, firefox-locale-ml, firefox-locale-it, firefox-locale-ia, firefox-locale-km, firefox-locale-eo, firefox-geckodriver, firefox-locale-bg, firefox-locale-si, firefox-locale-sq, firefox-locale-br, firefox-locale-sw, firefox-locale-csb, firefox-locale-oc, firefox-locale-ms, firefox-locale-th, firefox-locale-vi, firefox-locale-pa, firefox-locale-eu, firefox-locale-id, firefox-locale-kab, firefox-locale-ur, firefox-locale-is, firefox-locale-cs, firefox-locale-lv, firefox-locale-ja, firefox-locale-lg, firefox-locale-or, firefox-locale-cy, firefox-locale-mai, firefox-locale-mk, firefox-locale-bn, firefox-locale-as, firefox-locale-da, firefox-locale-hu, firefox-locale-sr, firefox-locale-nb, firefox-locale-an, firefox-locale-he, firefox-locale-zh-hant, firefox-locale-gn, firefox-locale-uz, firefox-locale-gu, firefox-locale-sk, firefox-locale-pt, firefox-locale-ar, firefox-locale-mn, firefox-locale-uk, firefox-locale-ko, firefox-locale-pl, firefox-locale-ne, firefox-locale-ku, firefox-locale-zh-hans, firefox-locale-nso, firefox-locale-fa, firefox-locale-en, firefox-locale-es, firefox-locale-de, firefox-locale-zu