Description
The SMB1 protocol implementation in Samba 4.x before 4.2.11, 4.3.x before 4.3.8, and 4.4.x before 4.4.2 does not recognize the "server signing = mandatory" setting, which allows man-in-the-middle attackers to spoof SMB servers by modifying the client-server data stream.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | samba | 2:4.3.7+dfsg-1 | — |
| Debian 13 | samba | 2:4.3.7+dfsg-1 | — |
| Debian 12 | samba | 2:4.3.7+dfsg-1 | — |
| Debian 8 | samba | 2:4.2.10+dfsg-0+deb8u1 | DSA-3548-1 |
| Debian 7 | samba | 2:3.6.6-6+deb7u9 | DSA-3548-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | samba | 2:4.3.8+dfsg-0ubuntu1 | — |
| Ubuntu 14.04 LTS | samba | 2:4.3.8+dfsg-0ubuntu0.14.04.2 | USN-2950-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | ctdb +26 | 4.2.10-6.el7_2 | RHSA-2016:0612 |
| RHEL 7 | ipa +6 | 4.2.0-15.el7_2.6.1 | RHSA-2016:0612 |
| RHEL 7 | libtdb +3 | 1.3.8-1.el7_2 | RHSA-2016:0612 |
| RHEL 7 | libtevent +2 | 0.9.26-1.el7_2 | RHSA-2016:0612 |
| RHEL 7 | openchange +3 | 2.0-10.el7_2 | RHSA-2016:0612 |
| RHEL 7 | pyldb +4 | 1.1.25-1.el7_2 | RHSA-2016:0612 |
| RHEL 7 | pytalloc +3 | 2.1.5-1.el7_2 | RHSA-2016:0612 |
| RHEL 6 | ipa +6 | 3.0.0-47.el6_7.2 | RHSA-2016:0612 |
| RHEL 6 | libtdb +3 | 1.3.8-1.el6_7 | RHSA-2016:0612 |
| RHEL 6 | libtevent +2 | 0.9.26-2.el6_7 | RHSA-2016:0612 |
| RHEL 6 | openchange +3 | 1.0-7.el6_7 | RHSA-2016:0612 |
| RHEL 6 | pyldb +4 | 1.1.25-2.el6_7 | RHSA-2016:0612 |
| RHEL 6 | pytalloc +3 | 2.1.5-1.el6_7 | RHSA-2016:0612 |
| RHEL 6 | samba4 +12 | 4.2.10-6.el6_7 | RHSA-2016:0612 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Rhel Mission Critical 6 | evolution-mapi +1 | 0.28.3-8.el6_2 | RHSA-2016:0620 |
| Red Hat Rhel Mission Critical 6 | openchange +3 | 1.0-1.el6_2 | RHSA-2016:0620 |
| Red Hat Rhel Mission Critical 6 | pyldb +4 | 1.1.25-2.el6_2 | RHSA-2016:0620 |
| Red Hat Rhel Mission Critical 6 | samba4 +3 | 4.2.10-6.el6_2 | RHSA-2016:0620 |
| Red Hat Rhel Mission Critical 6 | sssd +5 | 1.5.1-66.el6_2.5 | RHSA-2016:0620 |
| RHEL 7.1 EUS | ctdb +25 | 4.2.10-5.ael7b_1 | RHSA-2016:0618 |
| RHEL 7.1 EUS | ipa +2 | 4.1.0-18.ael7b_1.6 | RHSA-2016:0618 |
| RHEL 7.1 EUS | ipa-server +2 | 4.1.0-18.el7_1.6 | RHSA-2016:0618 |
| RHEL 7.1 EUS | libtdb +3 | 1.3.8-1.ael7b_1 | RHSA-2016:0618 |
| RHEL 7.1 EUS | libtevent +2 | 0.9.26-1.ael7b_1 | RHSA-2016:0618 |
| RHEL 7.1 EUS | openchange +3 | 2.0-4.ael7b_1.1 | RHSA-2016:0618 |
| RHEL 7.1 EUS | pyldb +4 | 1.1.25-1.ael7b_1 | RHSA-2016:0618 |
| RHEL 7.1 EUS | pytalloc +3 | 2.1.5-1.ael7b_1 | RHSA-2016:0618 |
| RHEL 7.1 EUS | samba-vfs-glusterfs | 4.2.10-5.el7_1 | RHSA-2016:0618 |
| RHEL 6.6 EUS | ipa +6 | 3.0.0-42.el6_6.1 | RHSA-2016:0620 |
| RHEL 6.6 EUS | openchange +3 | 1.0-7.el6_6 | RHSA-2016:0620 |
| RHEL 6.6 EUS | pyldb +4 | 1.1.25-2.el6_6 | RHSA-2016:0620 |
| RHEL 6.6 EUS | samba4 +12 | 4.2.10-6.el6_6 | RHSA-2016:0620 |
| RHEL 6.5 AUS | ipa +6 | 3.0.0-37.el6_5.1 | RHSA-2016:0620 |
| RHEL 6.5 AUS | openchange +3 | 1.0-7.el6_5 | RHSA-2016:0620 |
| RHEL 6.5 AUS | pyldb +4 | 1.1.25-2.el6_5 | RHSA-2016:0620 |
| RHEL 6.5 AUS | samba4 +12 | 4.2.10-6.el6_5 | RHSA-2016:0620 |
| RHEL 6.5 AUS | sssd +10 | 1.9.2-129.el6_5.7 | RHSA-2016:0620 |
| RHEL 6.4 AUS | ipa +6 | 3.0.0-26.el6_4.5 | RHSA-2016:0620 |
| RHEL 6.4 AUS | openchange +3 | 1.0-5.el6_4 | RHSA-2016:0620 |
| RHEL 6.4 AUS | pyldb +4 | 1.1.25-2.el6_4 | RHSA-2016:0620 |
| RHEL 6.4 AUS | samba4 +12 | 4.2.10-6.el6_4 | RHSA-2016:0620 |
| RHEL 6.4 AUS | sssd +10 | 1.9.2-82.12.el6_4 | RHSA-2016:0620 |
| Red Hat Gluster Storage 3 | ctdb +26 | 4.2.11-2.el6rhs | RHSA-2016:0614 |
| Red Hat Gluster Storage 3 | libtdb +3 | 1.3.8-1.el6rhs | RHSA-2016:0614 |
| Red Hat Gluster Storage 3 | libtevent +2 | 0.9.26-1.el6rhs | RHSA-2016:0614 |
| Red Hat Gluster Storage 3 | pyldb +4 | 1.1.24-1.el6rhs | RHSA-2016:0614 |
| Red Hat Gluster Storage 3 | pytalloc +3 | 2.1.5-1.el6rhs | RHSA-2016:0614 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | ctdb +26 | 4.2.10-6.el7_2 | ELSA-2016-0612 |
| Oracle Linux 7 | ipa-client +5 | 4.2.0-15.0.1.el7_2.6.1 | ELSA-2016-0612 |
| Oracle Linux 7 | ipa-server-selinux | 3.0.0-47.el6_7.2 | ELSA-2016-0612 |
| Oracle Linux 7 | libtdb +3 | 1.3.8-1.el7_2 | ELSA-2016-0612 |
| Oracle Linux 7 | libtevent +2 | 0.9.26-2.el6_7 | ELSA-2016-0612 |
| Oracle Linux 7 | openchange +3 | 2.0-10.el7_2 | ELSA-2016-0612 |
| Oracle Linux 7 | pyldb +4 | 1.1.25-2.el6_7 | ELSA-2016-0612 |
| Oracle Linux 7 | pytalloc +3 | 2.1.5-1.el7_2 | ELSA-2016-0612 |
| Oracle Linux 7 | samba4 +12 | 4.2.10-6.el6_7 | ELSA-2016-0612 |
Advisories 7
- RHSA-2016:0620 Red Hat Security Advisory: samba4 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2016:0618 Red Hat Security Advisory: samba security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2016:0614 Red Hat Security Advisory: samba security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2016:0612 Red Hat Security Advisory: samba and samba4 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- USN-2950-1 samba vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-3548-1 samba - security update Debian Security (DSA / DLA) · Mar 9, 2026
- ELSA-2016-0612 Critical: samba and samba4 security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Apr 12, 2016
References
- SSA:2016-106-02 vendor-advisory
- RHSA-2016:0612 vendor-advisory
- USN-2950-1 vendor-advisory
- 86011 vdb-entry
- http://badlock.org/
- https://www.samba.org/samba/security/CVE-2016-2114.html
- http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
- USN-2950-5 vendor-advisory
- https://www.samba.org/samba/history/samba-4.2.10.html
- FEDORA-2016-be53260726 vendor-advisory
- RHSA-2016:0618 vendor-advisory
- https://www.samba.org/samba/latest_news.html#4.4.2
- 1035533 vdb-entry
- FEDORA-2016-48b3761baa vendor-advisory
- RHSA-2016:0614 vendor-advisory
- RHSA-2016:0620 vendor-advisory
- openSUSE-SU-2016:1106 vendor-advisory
- https://bto.bluecoat.com/security-advisory/sa122
- USN-2950-3 vendor-advisory
- FEDORA-2016-383fce04e2 vendor-advisory
- openSUSE-SU-2016:1107 vendor-advisory
- GLSA-201612-47 vendor-advisory
- DSA-3548 vendor-advisory
- USN-2950-2 vendor-advisory
- USN-2950-4 vendor-advisory