Securing Network – Wireless – and Connected Infrastructures Fred Baumhardt Infrastructure Solutions Consulting Microsoft Security Solutions, Feb 4th, 2003

Agenda Defining the Datacenter Network Security Problem Penetration Techniques and Tools Network Defence-in-Depth Strategy Perimeter and Network Defences Operating System and Services Defences Application Defences Data Defences

The Datacenter Problem We All Face Systems organically grown under “Project” context No clear best practice from vendors Security often bolted on as an afterthought Fear of change – Time to Market Some Core Systems Extranets Internet Systems Project 1…n System Branch Offices Departments

The Big Picture of Security OS hardening is only one component of security strategy AND Firewalls are not a Panacea Entering the Bank Branch doesn’t get you into the vault Security relies on multiple things People and skills Process and incident management Internal Technologies – E.G. OS, Management Tools, switches, IDS, ISA Edge Technologies – Firewalls, ISA, IDS

Threat Modelling Internal Users are usually far more dangerous Normal employees have tools, experience, and know your systems – after all they use them Customers usually take little internal protection precautions – preferring to focus on external Firewalls, and DMZ scenarios for security Data is now being hacked – not just systems

The First Phase of Hacking Information Gathering and Intelligence Port Scanning – Banner Grabbing – TCP/IP Packet Profiling – TTL Packet Manipulating Researching network structure – newsgroup posts, outbound emails, these all hold clues to network design .

The Second Phase of Hacking Analysis of Collected Information Process relevant bits of data about target network Formulate an attack plan For Example: Attacker wont use SUN specific attacks on W2K Boxes, won’t use NT Attacks on .NET etc.. Hacker Forums, websites, exploit catalogues

The Third Phase of Hacking The Compromise OS Specific Attacks Denial of Service Attacks Application Attacks Buffer Overflows URL String Attacks Injection Cross-site Scripting Attacks Compromised system jumps into another

Networking and Security The network component is the single most important aspect to security Wireless is based on Radio transmission and reception – not bounded by wires Some sort of encryption is thus required to protect open medium Ethernet is also just about as insecure

Network Problems ctd Use encryption and authentication to control access to network WEP – Wired Equivalent Privacy 802.1X - using Public Key Cryptography Mutually authenticating client and network

Securing a Wireless Connection Three major strategies WEP – basic low security simple solution VPN – use an encrypted tunnel assuming network is untrusted 802.1X family – Use PKI to encrypt seamlessly from client to access point Usually complex to implement but then seamless to user Substantial investment in PKI Also vendor specific like Leap

What about the wired network ? This is where the hackers kill you Currently a “total trust” model You can ping HR database, or chairman's PC, or accounting system in Tokyo We assume anyone who can get in to our internal network is trusted – and well intentioned Ethernet and TCP/IP is fundamentally insecure

VPN Extend the “internal” network space to clients in internet Extends the security perimeter to the client Main systems are PPTP – L2TP/IPSEC IP Tunnel Corporate Net or Client Corporate Net in Reading Host A Host B Router C Router D Internet

How the Architecture Can Prevent Attack INTERNET Internet Remote data center Redundant Routers Redundant Firewalls Intrusion Detection BORDER NIC teams/2 switches VLAN VLAN VLAN VLAN Per imeter Client and Site VPN DNS & SMTP Proxy Redundant Internal Firewalls Infrastructure Network – Perimeter Active Directory NIC teams/2 switches INTERNAL VLAN VLAN VLAN VLAN Data Network – SQL Server Clusters Infrastructure Network – Internal Active Directory Messaging Network – Exchange VLAN VLAN VLAN VLAN . Client Network RADIUS Network Intranet Network - Web Servers Management Network – MOM, deployment

How do I do it ? A Flat DMZ Design to push intelligent inspection outwards ISA layer 7 filtration – RPC – SMTP – HTTP - Switches that act like firewalls IPSec where required between servers Group Policy to Manage Security 802.1X or VPN into ISA servers treating Wireless as Hostile Internal IDS installed TCP 443: HTTPS Or TCP 443: HTTPS Internet TCP 80: HTTP Stateful Packet Filtering Firewall Application Filtering Firewall (ISA Server) Exchange Server Wireless

Call To Action Take Action – your network transport is insecure Read and use security operations guides for each technology you use Mail me with questions – fredbaum@microsoft.com If I didn’t want to talk to you I would put a fake address Use the free MS tools to establish a baseline and stay on it Attack yourself – you will learn

Wherever you go – go securely ! ____________________________________________________________