Several security issues were fixed in Samba.
It was discovered that Samba did not automatically replicate ACLs set to inherit down a subtree on AD Directory, contrary to expectations. This issue was only addressed in Ubuntu 18.04 LTS, Ubuntu 19.04 and Ubuntu 19.10. (CVE-2019-14902)
21 January 2020
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in Samba.
It was discovered that Samba did not automatically replicate ACLs set to inherit down a subtree on AD Directory, contrary to expectations. This issue was only addressed in Ubuntu 18.04 LTS, Ubuntu 19.04 and Ubuntu 19.10. (CVE-2019-14902)
Robert Święcki discovered that Samba incorrectly handled certain character conversions when the log level is set to 3 or above. In certain environments, a remote attacker could possibly use this issue to cause Samba to crash, resulting in a denial of service. (CVE-2019-14907)
Christian Naumer discovered that Samba incorrectly handled DNS zone scavenging. This issue could possibly result in some incorrect data being written to the DB. This issue only applied to Ubuntu 19.04 and Ubuntu 19.10. (CVE-2019-19344)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.