SMB Signing not required

Medium Nessus Plugin ID 57608

Synopsis

Signing is not required on the remote SMB server.

Description

Signing is not required on the remote SMB server. An unauthenticated, remote attacker can exploit this to conduct man-in-the-middle attacks against the SMB server.

Solution

Enforce message signing in the host's configuration. On Windows, this is found in the policy setting 'Microsoft network server: Digitally sign communications (always)'. On Samba, the setting is called 'server signing'. See the 'see also' links for further details.

See Also

https://support.microsoft.com/en-us/help/887429/overview-of-server-message-block-signing

http://technet.microsoft.com/en-us/library/cc731957.aspx

http://www.nessus.org/u?74b80723

https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html

http://www.nessus.org/u?a3cac4ea

Plugin Details

Severity: Medium

ID: 57608

File Name: smb_signing_disabled.nasl

Version: 1.18

Type: remote

Family: Misc.

Published: 2012/01/19

Modified: 2018/11/15

Dependencies: 11153

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 5.3

Temporal Score: 4.6

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:microsoft:windows, cpe:/a:samba:samba

Vulnerability Publication Date: 2012/01/17