==========================================================================
Ubuntu Security Notice USN-4167-1
October 29, 2019

samba vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 19.10
- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Samba.

Software Description:
- samba: SMB/CIFS file, print, and login server for Unix

Details:

Michael Hanselmann discovered that the Samba client code incorrectly
handled path separators. If a user were tricked into connecting to a
malicious server, a remote attacker could use this issue to cause the
client to access local pathnames instead of network pathnames.
(CVE-2019-10218)

Simon Fonteneau and Björn Baumbach discovered that Samba incorrectly
handled the check password script. This issue could possibly bypass custom
password complexity checks, contrary to expectations. This issue only
affected Ubuntu 18.04 LTS, Ubuntu 19.04, and Ubuntu 19.10. (CVE-2019-14833)

Adam Xu discovered that Samba incorrectly handled the dirsync LDAP control.
A remote attacker with "get changes" permissions could possibly use this
issue to cause Samba to crash, resulting in a denial of service.
(CVE-2019-14847)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 19.10:
  libsmbclient                    2:4.10.7+dfsg-0ubuntu2.2
  samba                           2:4.10.7+dfsg-0ubuntu2.2

Ubuntu 19.04:
  libsmbclient                    2:4.10.0+dfsg-0ubuntu2.6
  samba                           2:4.10.0+dfsg-0ubuntu2.6

Ubuntu 18.04 LTS:
  libsmbclient                    2:4.7.6+dfsg~ubuntu-0ubuntu2.13
  samba                           2:4.7.6+dfsg~ubuntu-0ubuntu2.13

Ubuntu 16.04 LTS:
  libsmbclient                    2:4.3.11+dfsg-0ubuntu0.16.04.23
  samba                           2:4.3.11+dfsg-0ubuntu0.16.04.23

In general, a standard system update will make all the necessary changes.

References:
  https://usn.ubuntu.com/4167-1
  CVE-2019-10218, CVE-2019-14833, CVE-2019-14847

Package Information:
  https://launchpad.net/ubuntu/+source/samba/2:4.10.7+dfsg-0ubuntu2.2
  https://launchpad.net/ubuntu/+source/samba/2:4.10.0+dfsg-0ubuntu2.6
  https://launchpad.net/ubuntu/+source/samba/2:4.7.6+dfsg~ubuntu-0ubuntu2.13
  https://launchpad.net/ubuntu/+source/samba/2:4.3.11+dfsg-0ubuntu0.16.04.23