VNC Server Unauthenticated Access

high Nessus Plugin ID 26925
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The remote VNC server does not require authentication.


The VNC server installed on the remote host allows an attacker to connect to the remote host as no authentication is required to access this service.

** The VNC server sometimes sends the connected user to the XDM login
** screen. Unfortunately, Nessus cannot identify this situation.
** In such a case, it is not possible to go further without valid
** credentials and this alert may be ignored.


Disable the No Authentication security type.

Plugin Details

Severity: High

ID: 26925

File Name: vnc_no_auth.nasl

Version: Revision: 1.12

Type: remote

Family: Misc.

Published: 10/5/2007

Updated: 1/25/2013

Dependencies: vnc_security_types.nasl, os_fingerprint.nasl

Risk Information


Risk Factor: High

Base Score: 7.5

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

Vulnerability Information