[USN-3976-2] Samba vulnerability

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Ubuntu Security Notice USN-3976-2
May 14, 2019

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

- Ubuntu 14.04 ESM
- Ubuntu 12.04 ESM

Summary:

Samba could allow unintended access to network services.

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

Details:

USN-3976-1 fixed a vulnerability in Samba. This update provides
the corresponding update for Ubuntu 12.04 ESM and Ubuntu 14.04 ESM.

Original advisory details:

 Isaac Boukris and Andrew Bartlett discovered that Samba incorrectly
 checked S4U2Self packets. In certain environments, a remote attacker
 could possibly use this issue to escalate privileges.

Update instructions:

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

Ubuntu 14.04 ESM:
  samba                           2:4.3.11+dfsg-0ubuntu0.14.04.20+esm1

Ubuntu 12.04 ESM:
  samba                           2:3.6.25-0ubuntu0.12.04.18

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

References:
  https://usn.ubuntu.com/usn/usn-3976-2
  https://usn.ubuntu.com/usn/usn-3976-1
  CVE-2018-16860