Due to the continued incidents and
growing security risks from the service, access to CERN
using the VPN (Virtual Private
Network) service will be discontinued on Tuesday 29th
January 2008. In addition, new registrations will no
longer be accepted. Similar functionality to the VPN
service is provided by application gateways, such as WTS
(Windows Terminal Services) and the central Linux
service on LXPLUS. The recommended methods for
connecting to CERN from the Internet are documented at
http://cern.ch/security/Internet.
Motivation
The risk of
worms entering the CERN site from VPN connections is
high as they bypass the firewall protections in place
for standard Internet connections. The serious impact of
such incidents was already experienced in August 2003
when early versions of the Blaster worm rapidly entered
the site via VPN connections. Although protections were
added to contain those specific cases, the rise in zero
day exploits and home computers as a key target for
attackers is a dangerous combination, increasing the
risk of a similar such incidents occurring in future. In
addition to the increasing risks, the ability to make a
rapid follow up for VPN incidents is limited and does
not scale.
Known Issues
The closure of this service will
require a change of working habits for users not
familiar with the recommended methods for connecting to
CERN from the Internet. To ease this change a set of
FAQs has been prepared and
linked from
http://cern.ch/security/Internet.
The remaining known issues are
listed below:
- In some cases the alternative
working methods are less convenient and/or provide
reduced performance compared to VPN.
- Windows DFS File
synchronization is not possible from off-site
without VPN. File transfer (including mapping a
local disk to a WTS session) is possible.
- Remote installation of
software was possible with VPN. This practice is not
recommended therefore no alternative will be
provided. Users must instead bring their computers
physically to CERN.
If a case were
to arise where VPN is vital for the mission of the
organization and no alternative solution is available
within the timescale, a temporary extension could
possibly be maintained for the user concerned. This
would require that the case is justified and supported
by the user’s Department Head (or Deputy). The
configuration of the device and working method of the
user connecting to VPN would need to be agreed by a
member of the security team in order to minimise the
risk.
Questions not
addressed by the documentation referenced above can be
sent to
vpn.closure@cern.ch.