It was reported that various samba versions are vulnerable to man in the middle attack where attacker can intercept any DCERPC traffic between a client and a server in order to impersonate the client and get the same privileges as the authenticated user account. This is most problematic against active directory domain controllers. Description =========== The Security Account Manager Remote Protocol [MS-SAMR] and the Local Security Authority (Domain Policy) Remote Protocol [MS-LSAD] are both vulnerable to man in the middle attacks. Both are application level protocols based on the generic DCE 1.1 Remote Procedure Call (DCERPC) protocol. These protocols are typically available on all Windows installations as well as every Samba servers. They are used to maintain the Security Account Manager Database. This is applies to all roles, e.g. standalone, domain member, domain controller. Any authenticated DCERPC connection a client initiates against a server can be used by a man in the middle to impersonate the authenticated user against the SAMR or LSAD service on the server. The client choosen application protocol, auth type (e.g. Kerberos or NTLMSSP) and auth level (NONE, CONNECT, PKT_INTEGRITY, PKT_PRIVACY) does not matter in this case. As result a man in the middle is able to get read/write access to the Security Account Manager Database, which reveals all passwords and any other potential sensitive information. Workaround ========== You may lower risk by avoiding to login/authenticate with privileged accounts over unprotected networks. Privileged accounts should only be used on the physical console (server) console, so that authentication does not involve any network communication. If the machine is acting as client workstation you may restrict any incoming network traffic by a firewall. External Reference: https://access.redhat.com/articles/2243351 https://access.redhat.com/articles/2253041 http://badlock.org/
Acknowledgments: Name: the Samba project Upstream: Stefan Metzmacher (SerNet)
Public via: https://www.samba.org/samba/security/CVE-2016-2118.html
Created samba tracking bugs for this issue: Affects: fedora-all [bug 1326453]
This issue has been addressed in the following products: Red Hat Enterprise Linux 6 Via RHSA-2016:0611 https://rhn.redhat.com/errata/RHSA-2016-0611.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 5 Via RHSA-2016:0613 https://rhn.redhat.com/errata/RHSA-2016-0613.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 5 Via RHSA-2016:0621 https://rhn.redhat.com/errata/RHSA-2016-0621.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 5.6 Long Life Red Hat Enterprise Linux 5.9 Long Life Via RHSA-2016:0624 https://rhn.redhat.com/errata/RHSA-2016-0624.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 5.6 Long Life Red Hat Enterprise Linux 5.9 Long Life Via RHSA-2016:0623 https://rhn.redhat.com/errata/RHSA-2016-0623.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 6.4 Advanced Update Support Red Hat Enterprise Linux 6.2 Advanced Update Support Red Hat Enterprise Linux 6.6 Extended Update Support Red Hat Enterprise Linux 6.5 Advanced Update Support Via RHSA-2016:0619 https://rhn.redhat.com/errata/RHSA-2016-0619.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 4 Extended Lifecycle Support Via RHSA-2016:0625 https://rhn.redhat.com/errata/RHSA-2016-0625.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 6.6 Extended Update Support Red Hat Enterprise Linux 6.5 Advanced Update Support Red Hat Enterprise Linux 6.4 Advanced Update Support Red Hat Enterprise Linux 6.2 Advanced Update Support Via RHSA-2016:0620 https://rhn.redhat.com/errata/RHSA-2016-0620.html
This issue has been addressed in the following products: Red Hat Gluster Storage 3.1 for RHEL 7 Red Hat Gluster Storage 3.1 for RHEL 6 Via RHSA-2016:0614 https://rhn.redhat.com/errata/RHSA-2016-0614.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 6 Via RHSA-2016:0612 https://rhn.redhat.com/errata/RHSA-2016-0612.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 7.1 Extended Update Support Via RHSA-2016:0618 https://rhn.redhat.com/errata/RHSA-2016-0618.html
samba-4.3.8-0.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.
samba-4.2.11-0.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.
samba-4.4.2-1.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.