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Home >> Browse Vulnerability Assessment Database >> Misc. >> RealVNC Authentication Bypass Vulnerability

Vulnerability Assessment Details

RealVNC Authentication Bypass Vulnerability

Vulnerability Assessment Summary
Tries to bypass authentication using RealVNC

Detailed Explanation for this Vulnerability Assessment

Summary :

The remote VNC server is prone to an authentication bypass issue.

Description :

The remote host appears to be running RealVNC, a VNC server for
Windows and Linux/unix platforms.

The version of RealVNC installed on the remote host permits a possible hacker
to bypass authentication by simply requesting 'Type 1 - None' as the
authentication type even though it is not explicitly configured to
support that. By exploiting this issue, a possible hacker gains access to
the affected host at the privilege level under which RealVNC operates,
typically as Administrator under Windows.

See also :

http://www.intelliadmin.com/blog/2006/05/security-flaw-in-realvnc-411.html
http://lists.grok.org.uk/pipermail/full-disclosure/2006-May/046039.html
http://www.realvnc.com/products/free/4.1/release-notes.html
http://www.realvnc.com/products/personal/4.2/release-notes.html
http://www.realvnc.com/products/enterprise/4.2/release-notes.html

Solution :

Upgrade to RealVNC Free Edition 4.1.2 / Personal Edition 4.2.3 /
Enterprise Edition 4.2.3 or later.

Network Security Threat Level:

High / CVSS Base Score : 7.0
(AV:R/AC:L/Au:NR/C:P/I:P/A:P/B:N)

Networks Security ID: 17978

Vulnerability Assessment Copyright: This script is Copyright (C) 2006 Tenable Network Security

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