It is possible to spoof the sender's email address and display an arbitrary sender address to the email recipient. The real sender's address is not displayed if preceded by a null character in the display string. This vulnerability affects Thunderbird < 52.5.2.
http://www.securityfocus.com/bid/102258
http://www.securitytracker.com/id/1040123
https://access.redhat.com/errata/RHSA-2018:0061
https://bugzilla.mozilla.org/show_bug.cgi?id=1423432
https://lists.debian.org/debian-lts-announce/2017/12/msg00026.html
https://usn.ubuntu.com/3529-1/
Source: MITRE
Published: 2018-06-11
Updated: 2018-08-07
Type: CWE-20
Base Score: 5
Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N
Impact Score: 2.9
Exploitability Score: 10
Severity: MEDIUM
Base Score: 5.3
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Impact Score: 1.4
Exploitability Score: 3.9
Severity: MEDIUM