http://www.techworld.com/security/news/index.cfm?newsID=11663
By John E. Dunn
Techworld
10 March 2008
Many companies running BlackBerry Enterprise Server (BES) could be
inadvertently opening a door to attackers, a penetration testing company
has found.
Penetration testing consultancy NTA Monitor found that most of its
customers running the BlackBerry Server with Microsoft Exchange were
taking the path of least resistance by opening unencrypted ports from
the heart of their network to service providers. The providers, in turn,
opened a return back to the BES that would pass through firewalls
without any policies being applied.
This left the network open on several levels, including session
hijacking, IP spoofing, or just the interception of unencrypted traffic.
"A hacker could potentially use this back channel to move around inside
an organisation undetected, removing confidential information or
installing malware on to the network," said Roy Hills, NTA's technical
director.
According to NTA Monitor's technical manager, Adrian Goodhead, the open
configuration was no accident of poor implementation, accounting for a
sizeable 10-15 of the company's enterprise-level customers using
BlackBerry handhelds (roughly 70-80 percent of the total base they
surveyed). The commonest cause was simply cost.
The company recommends implementing a BES in a demilitarised zone (DMZ),
which would isolate attacks against the sever from the wider network.
However, this added complexity, and added complexity added expense.
"You have to add various software and hardware. People are trying to
keep costs down," said Goodhead.
He characterised the flaw as low-to-medium in severity because "it
requires a fair amount of knowledge" to exploit, but nevertheless one
that needed to be addressed.
Goodhead criticised the service providers for not explaining that a more
expensive implementation was usually necessary for security reasons.
BlackBerry, for its part, gave details of how to implement its
technology securely, he said, and so couldn't be blamed.
NTA Monitor, which recently found holes in VPNs, offers several general
security recommendations for clients using BES. These include using SSL
encryption, enabling content protection on the handheld, disallowing
non-approved applications – including P2P messaging – and turning off
Bluetooth on the handheld.
___________________________________________________
Subscribe to InfoSec News
http://www.infosecnews.org/mailman/listinfo/isn
