Microsoft Windows SMB NULL Session Authentication
high Nessus Plugin ID 26920
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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?e32d594f
Plugin Details
Severity: High
ID: 26920
File Name: smb_null_session.nasl
Version: 1.38
Type: remote
Agent: windows
Family: Windows
Published: 10/4/2007
Updated: 1/11/2022
Dependencies: smb_login.nasl
Risk Information
CVSS Score Source: CVE-2019-0519
VPR
Risk Factor: Medium
Score: 5.8
CVSS v2
Risk Factor: High
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
CVSS v3
Risk Factor: High
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_suspected
Vulnerability Publication Date: 7/14/1999
Reference Information
BID: 494