Microsoft pptp vpn vulnerabilities Exploits in Action

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Key fingerprint = AF19 FA27 2F94 998D FDB5 DE3D F8B5 06E4 A169 4E46 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Key fingerprint = AF19 FA27 2F94 998D FDB5 DE3D F8B5 06E4 A169 4E46 
 
© SANS Institute 2000 - 200
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Author retains full rights.
9
Topology 6
Wireless (such as the popular 802.11b technologies) usage of VPN, 
usually one of the previous 5 topologies and possibly a firewall (recommended). 
Unfortunately most companies are NOT implementing firewalls or VPNs 
to separate and protect their wireless LAN users, despite repeated press 
releases and proof of the simplicity of compromise. However, for those that do 
heed such warnings, this is one option, of several to choose from, that many 
implement. It’s fairly easy to setup. It’s much along the lines of Topology 1, 
because most companies assume that there are far fewer attacks via their local 
wireless LAN than the Internet just because of the sheer numbers of nodes, 
unfortunately such assumptions tend to be perilous. Others opt to have a firewall 
in front of the VPN server as well as the LAN, but this does not yet appear to be 
a common practice.
Advantages: More secure wireless setup, fairly easy to setup and 
administrate
Disadvantages: VPN server still wide open to many attacks and 
information leakage to wireless LAN users. Every attack described in this 
document is very effective on such a network. Even if the attacker can’t gain 
VPN access into the LAN, they can still possibly easily abuse the bandwidth on 
the wireless segment, and easily attack the server and users on this segment.