Ubuntu Security Notice USN-4540-1
September 24, 2020
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 18.04 LTS
Several security issues were fixed in atftpd.
– atftp: Advanced TFTP Server and Client
Denis Andzakovic discovered that atftpd incorrectly handled certain
malformed packets. A remote attacker could send a specially crafted packet
to cause atftpd to crash, resulting in a denial of service.
Denis Andzakovic discovered that atftpd did not properly lock the thread
list mutex. An attacker could send a large number of tftpd packets
simultaneously when running atftpd in daemon mode to cause atftpd to
crash, resulting in a denial of service. (CVE-2019-11366)
The problem can be corrected by updating your system to the following
Ubuntu 18.04 LTS:
In general, a standard system update will make all the necessary changes.