Open Stack

It is also worth noting here for future reference that the above 2
patches:

https://review.openstack.org/169752
https://review.openstack.org/169753

are relevant to Kilo only (they will not be backported to previous
releases). In Kilo it will no longer be needed to keep the
novncproxy_base_url options in sync between compute and novncproxy
services. This is because the URL a token was authorized for will be
kept alongside other authorization info.

However there is a caveat to the way upgrades need to be done for Juno
to Kilo (it copied here from the original commit message):

UpgradeImpact: Websocket proxies need to be upgraded in a lockstep
with the API nodes up to this commit (or when upgrading to Kilo),
as older API nodes will not be sending the access_url when authorizing
console access, and newer proxy services (this commit and onward) would
fail to authorize such requests.

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Security, which is subscribed to OpenStack.
https://bugs.launchpad.net/bugs/1409142

Title:
  [OSSA 2015-005] Websocket Hijacking Vulnerability in Nova VNC Server
  (CVE-2015-0259)

Status in OpenStack Compute (Nova):
  Fix Released
Status in OpenStack Compute (nova) icehouse series:
  Fix Released
Status in OpenStack Compute (nova) juno series:
  Fix Released
Status in OpenStack Security Advisories:
  Fix Released

Bug description:
  OpenStack Vulnerability Team:

  Brian Manifold (bmanifol at cisco.com) from Cisco has discovered a
  vulnerability in the Nova VNC server implementation. We have a patch for
  this vulnerability and consider this a very high risk.

  Please email Dave McCowan (dmccowan at cisco.com) for more details on the
  attached patch.

  Issue Details:

  Horizon uses a VNC client which uses websockets to pass information.  The
  Nova VNC server does not validate the origin of the websocket request,
  which allows an attacker to make a websocket request from another domain.
  If the victim opens both an attacker's site and the VNC console
  simultaneously, or if the victim has recently been using the VNC console
  and then visits the attacker's site, the attacker can make a websocket
  request to the Horizon domain and proxy the connection to another
  destination.

  This gives the attacker full read-write access to the VNC console of any
  instance recently accessed by the victim.

  Recommendation:
   Verify the origin field in request header on all websocket requests.

  Threat:
        CWE-345
   * Insufficient Verification of Data Authenticity -- The software does not
  sufficiently verify the origin or authenticity of data, in a way that
  causes it to accept invalid data.

        CWE-346
   * Origin Validation Error -- The software does not properly verify that
  the source of data or communication is valid.

        CWE-441
   * Unintended Proxy or Intermediary ('Confused Deputy') -- The software
  receives a request, message, or directive from an upstream component, but
  the software does not sufficiently preserve the original source of the
  request before forwarding the request to an external actor that is outside
  of the software's control sphere. This causes the software to appear to be
  the source of the request, leading it to act as a proxy or other
  intermediary between the upstream component and the external actor.

  Steps to reproduce:
   1. Login to horizon
   2. Pick an instance, go to console/vnc tab, wait for console to be loaded
   3. In another browser tab or window, load a VNC console script from local
  disk or remote site
   4. Point the newly loaded VNC console to the VNC server and a connection
  is made
  Result:
   The original connection has been been hijacked by the second connection

  Root cause:
   Cross-Site WebSocket Hijacking is concept that has been written about in
  various security blogs.
  One of the recommended countermeasures is to check the Origin header of
  the WebSocket handshake request.

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