Microsoft Windows SMB NULL Session Authentication
high Nessus Plugin ID 26920
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VPR Score: 5.8
Synopsis
It is possible to log into the remote Windows host with a NULL session.Description
The remote host is running Microsoft Windows. It is possible to log into it using a NULL session (i.e., with no login or password).Depending on the configuration, it may be possible for an unauthenticated, remote attacker to leverage this issue to get information about the remote host.
Solution
Apply the following registry changes per the referenced Technet advisories :Set :
- HKLM\SYSTEM\CurrentControlSet\Control\LSA\RestrictAnonymous=1
- HKLM\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters\restrictnullsessaccess=1
Reboot once the registry changes are complete.
See Also
http://www.nessus.org/u?5c2589f6
Plugin Details
Severity: High
ID: 26920
File Name: smb_null_session.nasl
Version: 1.35
Type: remote
Agent: windows
Family: Windows
Published: 10/4/2007
Updated: 9/2/2020
Dependencies: smb_login.nasl
Risk Information
Risk Factor: High
VPR Score: 5.8
CVSS Score Source: CVE-2019-0519
CVSS v2.0
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
CVSS v3.0
Base Score: 7.3
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Vulnerability Information
CPE: cpe:/o:microsoft:windows
Required KB Items: SMB/null_session_enabled
Vulnerability Publication Date: 7/14/1999
Reference Information
BID: 494