VNC Server Unauthenticated Access

high Nessus Plugin ID 26925
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote VNC server does not require authentication.

Description

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.

Solution

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

CVSS v2

Risk Factor: High

Base Score: 7.5

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

Vulnerability Information