Description
libcli/smb/smbXcli_base.c in Samba 4.x before 4.2.14, 4.3.x before 4.3.11, and 4.4.x before 4.4.5 allows man-in-the-middle attackers to bypass a client-signing protection mechanism, and consequently spoof SMB2 and SMB3 servers, via the (1) SMB2_SESSION_FLAG_IS_GUEST or (2) SMB2_SESSION_FLAG_IS_NULL flag.
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 | 2:4.4.5+dfsg-1 | — |
| Debian 13 | samba | 2:4.4.5+dfsg-1 | — |
| Debian 12 | samba | 2:4.4.5+dfsg-1 | — |
| Debian 8 | samba | 2:4.2.14+dfsg-0+deb8u2 | DSA-3740-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | samba | 2:4.3.11+dfsg-0ubuntu0.16.04.1 | USN-3092-1 |
| Ubuntu 14.04 LTS | samba | 2:4.3.11+dfsg-0ubuntu0.14.04.1 | USN-3092-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | ctdb +26 | 4.2.10-7.el7_2 | RHSA-2016:1486 |
| RHEL 6 | samba4 +12 | 4.2.10-7.el6_8 | RHSA-2016:1487 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Gluster Storage 3 | ctdb +24 | 4.4.3-8.el6rhs | RHSA-2016:1494 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP1 | samba | 4.2.4-26.2 | SUSE-SU-2016:2306-1 |
| SLES 12 | samba | 4.2.4-18.27.9 | SUSE-SU-2016:2570-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP1 | samba | 4.2.4-26.2 | SUSE-SU-2016:2306-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | samba | 4.5.0-1.1 | openSUSE-SU-2024:10069-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | ctdb +26 | 4.2.10-7.el7_2 | ELSA-2016-1486 |
Advisories 9
- RHSA-2016:1487 Red Hat Security Advisory: samba4 security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2016:1494 Red Hat Security Advisory: samba security update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- RHSA-2016:1486 Red Hat Security Advisory: samba security and bug fix update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- USN-3092-1 samba vulnerability Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-3740-1 samba - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2016:2570-1 Security update for samba SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10069-1 ctdb-4.5.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:2306-1 Security update for samba SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2016-1486 Moderate: samba security and bug fix update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jul 26, 2016
References
- http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
- RHSA-2016:1494 vendor-advisory
- 91700 vdb-entry
- RHSA-2016:1486 vendor-advisory
- GLSA-201805-07 vendor-advisory
- openSUSE-SU-2016:1830 vendor-advisory
- RHSA-2016:1487 vendor-advisory
- 1036244 vdb-entry
- https://www.samba.org/samba/security/CVE-2016-2119.html