==========================================================================
Ubuntu Security Notice USN-2950-5
May 25, 2016

samba regression
==========================================================================

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

- Ubuntu 16.04 LTS
- Ubuntu 15.10
- Ubuntu 14.04 LTS

Summary:

USN-2950-1 introduced a regression in Samba.

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

Details:

USN-2950-1 fixed vulnerabilities in Samba. USN-2950-3 updated Samba to
version 4.3.9, which introduced a regression when using the ntlm_auth tool.
This update fixes the problem.

Original advisory details:

 Jouni Knuutinen discovered that Samba contained multiple flaws in the
 DCE/RPC implementation. A remote attacker could use this issue to perform
 a denial of service, downgrade secure connections by performing a man in
 the middle attack, or possibly execute arbitrary code. (CVE-2015-5370)
  Stefan Metzmacher discovered that Samba contained multiple flaws in the
 NTLMSSP authentication implementation. A remote attacker could use this
 issue to downgrade connections to plain text by performing a man in the
 middle attack. (CVE-2016-2110)
  Alberto Solino discovered that a Samba domain controller would establish a
 secure connection to a server with a spoofed computer name. A remote
 attacker could use this issue to obtain sensitive information.
 (CVE-2016-2111)
  Stefan Metzmacher discovered that the Samba LDAP implementation did not
 enforce integrity protection. A remote attacker could use this issue to
 hijack LDAP connections by performing a man in the middle attack.
 (CVE-2016-2112)
  Stefan Metzmacher discovered that Samba did not validate TLS certificates.
 A remote attacker could use this issue to spoof a Samba server.
 (CVE-2016-2113)
  Stefan Metzmacher discovered that Samba did not enforce SMB signing even if
 configured to. A remote attacker could use this issue to perform a man in
 the middle attack. (CVE-2016-2114)
  Stefan Metzmacher discovered that Samba did not enable integrity protection
 for IPC traffic. A remote attacker could use this issue to perform a man in
 the middle attack. (CVE-2016-2115)
  Stefan Metzmacher discovered that Samba incorrectly handled the MS-SAMR and
 MS-LSAD protocols. A remote attacker could use this flaw with a man in the
 middle attack to impersonate users and obtain sensitive information from
 the Security Account Manager database. This flaw is known as Badlock.
 (CVE-2016-2118)
  Samba has been updated to 4.3.8 in Ubuntu 14.04 LTS and Ubuntu 15.10.
 Ubuntu 12.04 LTS has been updated to 3.6.25 with backported security fixes.
  In addition to security fixes, the updated packages contain bug fixes,
 new features, and possibly incompatible changes. Configuration changes may
 be required in certain environments.

Update instructions:

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

Ubuntu 16.04 LTS:
  samba                           2:4.3.9+dfsg-0ubuntu0.16.04.2

Ubuntu 15.10:
  samba                           2:4.3.9+dfsg-0ubuntu0.15.10.2

Ubuntu 14.04 LTS:
  samba                           2:4.3.9+dfsg-0ubuntu0.14.04.3

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

References:
  http://www.ubuntu.com/usn/usn-2950-5
  http://www.ubuntu.com/usn/usn-2950-1
  https://launchpad.net/bugs/1578576

Package Information:
  https://launchpad.net/ubuntu/+source/samba/2:4.3.9+dfsg-0ubuntu0.16.04.2
  https://launchpad.net/ubuntu/+source/samba/2:4.3.9+dfsg-0ubuntu0.15.10.2
  https://launchpad.net/ubuntu/+source/samba/2:4.3.9+dfsg-0ubuntu0.14.04.3