CVE-2016-2123.html:

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== Subject:     Samba NDR Parsing ndr_pull_dnsp_name Heap-based Buffer
==              Overflow Remote Code Execution Vulnerability
==
== CVE ID#:     CVE-2016-2123
== ZDE ID#:     ZDI-CAN-3995
==
== Versions:    Samba 4.0.0 to 4.5.2
==
== Summary:     Authenicated users can supply malicious dnsRecord attributes
==              on DNS objects and trigger a controlled memory corruption.
==
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===========
Description
===========

The Samba routine ndr_pull_dnsp_name contains an integer wrap problem,
leading to an attacker-controlled memory overwrite. ndr_pull_dnsp_name
parses data from the Samba Active Directory ldb database.  Any user
who can write to the dnsRecord attribute over LDAP can trigger this
memory corruption.

By default, all authenticated LDAP users can write to the dnsRecord
attribute on new DNS objects. This makes the defect a remote privilege
escalation.

==================
Patch Availability
==================

A patch addressing this defect has been posted to

  https://www.samba.org/samba/security/

Additionally, Samba 4.5.3, 4.4.8 and 4.3.13 have been issued as
security releases to correct the defect. Samba vendors and administrators
running affected versions are advised to upgrade or apply the patch as
soon as possible.

==========
Workaround
==========

It is possible to change the ntSecurityDescriptor on DNS zones, but
this will impact on the expected behaviour of the AD Domain.

=======
Credits
=======

This vulnerability was detected and reported to the Samba developers
by Trend Micro's Zero Day Initiative and Frederic Besler.