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Gentoo Linux Security Advisory                           GLSA 202411-01
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                                           https://security.gentoo.org/
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 Severity: High
    Title: Neat VNC: Authentication Bypass
     Date: November 06, 2024
     Bugs: #937140
       ID: 202411-01

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Synopsis
========

A vulnerability has been discovered in Neat VNC, which can lead to
authentication bypass.

Background
==========

Neat VNC is a liberally licensed VNC server library that's intended to
be fast and neat.

Affected packages
=================

Package           Vulnerable    Unaffected
----------------  ------------  ------------
gui-libs/neatvnc  < 0.8.1       >= 0.8.1

Description
===========

Neat VNC allows remote attackers to bypass authentication via a request
in which the client specifies an insecure security type such as "Type 1
- None", which is accepted even if it is not offered by the server, as
originally demonstrated using a long password.

Impact
======

A remote attacker can opt not to use any authentication method and
access the VNC server.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All Neat VNC users should upgrade to the latest version:

  # emerge --sync
  # emerge --ask --oneshot --verbose ">=gui-libs/neatvnc-0.8.1"

References
==========


Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

 https://security.gentoo.org/glsa/202411-01

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
https://bugs.gentoo.org.

License
=======

Copyright 2024 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

https://creativecommons.org/licenses/by-sa/2.5