INFORMATION SECURITY MANAGEMENT

LECTURE 9: PROTECTION MECHANISMS

You got to be careful if you don’t know where you’re going, because you might not get there. – Yogi Berra

Hacking NetworksPhase 1: Reconnaissance Physical Break-In Dumpster Diving Google, Newsgroups,

Web sites Social Engineering

Phishing: fake email Pharming: fake web

pages WhoIs Database Domain Name Server

Interrogations

Registrant: Microsoft Corporation One Microsoft Way Redmond, WA 98052 US

Domain name: MICROSOFT.COM

Administrative Contact: Administrator, Domain domains@microsoft.com One Microsoft Way Redmond, WA 98052 US +1.4258828080 Technical Contact: Hostmaster, MSN msnhst@microsoft.com One Microsoft Way Redmond, WA 98052 US +1.4258828080

Registration Service Provider: DBMS VeriSign, dbms-support@verisign.com 800-579-2848 x4 Please contact DBMS VeriSign for domain updates,

DNS/Nameserver changes, and general domain support questions.

Registrar of Record: TUCOWS, INC. Record last updated on 27-Aug-2006. Record expires on 03-May-2014. Record created on 02-May-1991.

Domain servers in listed order: NS3.MSFT.NET 213.199.144.151 NS1.MSFT.NET 207.68.160.190 NS4.MSFT.NET 207.46.66.126 NS2.MSFT.NET 65.54.240.126 NS5.MSFT.NET 65.55.238.126

Hacking NetworksPhase 2: ScanningWar Driving: Can I find a wireless network?

War Dialing: Can I find a modem to connect to?

Network Mapping: What IP addresses exist, and what ports are open on them?

Vulnerability-Scanning Tools: What versions of software are implemented on devices?

Passive Attacks

Eavesdropping: Listen to packets from other parties = Sniffing

Traffic Analysis: Learn about network from observing traffic patterns

Footprinting: Test to determine software installed on system = Network Mapping

Hacking Networks:Phase 3: Gaining Access

Network Attacks: Sniffing

(Eavesdropping) IP Address Spoofing Session Hijacking

System Attacks: Buffer Overflow Password Cracking SQL Injection Web Protocol Abuse Denial of Service Trap Door Virus, Worm, Trojan

horse,

Some Active Attacks

Denial of Service: Message did not make it; or service could not run

Masquerading or Spoofing: The actual sender is not the claimed sender

Message Modification: The message was modified in transmission

Packet Replay: A past packet is transmitted again in order to gain access or otherwise cause damage

Man-in-the-Middle Attack

10.1.1.1

10.1.1.2

10.1.1.3

(1) Login

(3) Password

(2) Login

(4) Password

Hacking Networks:Phase 4: Exploit/Maintain Access

Backdoor

Trojan Horse

Spyware/AdwareBots

User-Level Rootkit

Kernel-Level Rootkit

Replaces systemexecutables: e.g. Login, ls, du

Replaces OS kernel:e.g. process or filecontrol to hide

Control system:system commands,log keystrokes, pswd

Useful utility actuallycreates a backdoor.

Slave forwards/performscommands; spreads,list email addrs, DOSattacks

Spyware: Collect info:keystroke logger,collect credit card #s,AdWare: insert ads,filter search results

Botnets

AttackerHandler

Bots: Host illegal movies, music, pornography, criminal web sites, … Forward Spam for financial gain

China Hungary

Botnets: Bots

Zombies

Distributed Denial of Service

Zombies

VictimAttackerHandler

Can barrage a victimserver with requests,causing the networkto fail to respond to anyone

Russia Bulgaria UnitedStates

Zombies

Introduction

• Threats -> Vulnerabilities -> Risk ->Controls

• Technical controls– Must be combined with sound policy and

education, training, and awareness efforts

• Examples of technical security mechanisms

Sphere of Protection

Management of Information Security, 3rd ed.

Source: Course Technology/Cengage Learning

Access Controls

• The four processes of access control– Identification– Authentication– Authorization– Accountability

• A successful access control approach always incorporates all four of these elements

Table 10-1 Password power

Source: Course Technology/Cengage Learning

Access Controls – Password Strength

Acceptability of Biometrics

• Note: Iris Scanning has experienced rapid growth in popularity and due to it’s acceptability, low cost, and effective security

Google Offers New Alternative for Biometrics

Firewalls

• Any device that prevents a specific type of information from moving between two networks

Types:• Packet Filtering• Application Level• Stateful Inspection Firewalls

The Development of Firewalls

• Packet filtering firewalls– Simple networking devices that filter packets by

examining every incoming and outgoing packet header

The Development of Firewalls

• Packet filtering firewalls

The Development of Firewalls

• Application-level firewalls – Consists of dedicated computers kept separate

from the first filtering router (edge router)

– Commonly used in conjunction with a second or internal filtering router - or proxy server

– Implemented for specific protocols

The Development of Firewalls

• Application-level firewalls

The Development of Firewalls

• Stateful inspection firewalls – Keeps track of each network connection

established between internal and external systems using a state table

– Can restrict incoming packets by allowing access only to packets that constitute responses to requests from internal hosts

FirewallConfigurations

A A

terminal

firewall

hostRouter Packet Filtering:Packet header is inspectedSingle packet attacks caughtVery little overhead in firewall: very quickHigh volume filter

A A

terminal

firewall

host

A

Stateful InspectionState retained in firewall memoryMost multi-packet attacks caughtMore fields in packet header inspectedLittle overhead in firewall: quick

FirewallConfigurations

A B

terminal

firewall

host

A

Application-Level FirewallPacket session terminated and recreated via a Proxy ServerPacket header completely inspectedMost or all of application inspectedHighest overhead: slow & low volume

B

Firewall Architectures

• Each firewall generation can be implemented in several architectural configurations

• Common architectural implementations– Packet filtering routers– Screened-host firewalls– Dual-homed host firewalls– Screened-subnet firewalls

Firewall Architectures:Packet filtering routers

Most organizations with an Internet connection use some form of router between their internal networks and the external service provider

Firewall Architectures:Screened-host firewall systems

• Combine the packet filtering router with a separate, dedicated firewall such as an application proxy server

Firewall Architectures:Dual-Homed host firewalls

• The bastion host contains two network interfaces1. One is connected to the external network2. One is connected to the internal network

Selecting the Right Firewall

• Firewall Technology• Cost• Maintenance • Future Growth

Managing Firewalls

• Any firewall device must have its own configuration

• Firewall Rules

• Policy regarding firewall use

Managing Firewalls (cont’d.)

• Firewall best practices– All traffic from the trusted network allowed out– The firewall is never accessible directly from the

public network– Email Policies

Intrusion Detection and Prevention Systems (IDPS)

• The term intrusion detection/prevention system (IDPS) can be used to describe current anti-intrusion technologies

• Like firewall systems, IDPSs require complex configurations to provide the level of detection and response desired

Intrusion Detection and Prevention Systems (cont’d.) IDPS technologies can respond to a detected

threat by attempting to prevent it from succeeding

Different Response Techniques IDS vs. IPS

Network or Host Based Protection

IDPS – Host vs. Network

http://www.windowsecurity.com/articles-tutorials/intrusion_detection/Hids_vs_Nids_Part1.html

Intrusion Detection Systems (IDS) Intrusion Prevention Systems (IPS)

Network IDS=NIDS Examines packets for attacks Can find worms, viruses, org-

defined attacks Warns administrator of attack IPS=Packets are routed

through IPS

Host IDS=HIDS Examines actions or resources

for attacks Recognize unusual or

inappropriate behavior E.g., Detect modification or

deletion of special files

Router

Firewall

IDS

Signature-Based IDPS

• Examines data traffic for something that matches the preconfigured, predetermined attack pattern signatures

• Weakness: slow and methodical attacks may slip undetected through the IDPS, as their actions may not match a signature that includes factors based on duration of the events

Statistical Anomaly-Based IDPS

• First collects data from normal traffic and establishes a baseline– Then periodically samples network activity, based

on statistical methods, and compares the samples to the baseline

• Advantage: Able to detect new types of attacks, because it looks for abnormal activity of any type

Managing Intrusion Detection and Prevention Systems

• IDPSs must be configured to differentiate between routine circumstances and low, moderate, or severe threats

• A properly configured IDPS can translate a security alert into different types of notifications

• Most IDPSs monitor systems using agents

• Consolidated enterprise manager

Honeypot & Honeynet

Honeypot: A system with a special software application which appears easy to break into

Honeynet: A network which appears easy to break into Purpose: Catch attackers All traffic going to honeypot/net is suspicious If successfully penetrated, can launch further attacks Must be carefully monitored

External DNS

IDS Web Server

E-Commerce VPNServer

Firewall

HoneyPot

Remote Access Protection

• Network connectivity using external connections – Usually much simpler and less sophisticated than

Internet connections

– Simple user name and password schemes are usually the only means of authentication

RADIUS and TACACS

• Systems that authenticate the credentials of dial-up access users

• Typical dial-up systems place the authentication of users on the system connected to the modems

• Options: • Remote Authentication Dial-In User Service (RADIUS) • Terminal Access Controller Access Control(TACACS)

Authentication Protocols

RADIUS Over-the-wire protocol from client

to AAA (authentication, authorization, accounting) server

TACACS Between access point or gateway and

an AAA server Replaced by TACACS+ and RADIUS

RADIUS and TACACS (cont’d.)

Source: Course Technology/Cengage Learning

Managing Connections

• Organizations that continue to offer remote access must:– Determine how many connections the

organization has– Control access to authorized modem numbers – Use call-back whenever possible– Use token-based authentication if at all

possible

Wireless Networking Protection

• Use IEEE 802.11 protocol

• War driving– Moving through a geographic area or building,

actively scanning for open or unsecured WAPs

• Common encryption protocols used to secure wireless networks– Wired Equivalent Privacy (WEP) – Wi-Fi Protected Access (WPA)

Wired Equivalent Privacy (WEP)

• Provides a basic level of security to prevent unauthorized access or eavesdropping

• Fundamental Cryptological Flaws– Resulting in vulnerabilities that can be exploited,

which led to replacement by WPA

Wi-Fi Protected Access (WPA)

• WPA is an industry standard

• IEEE 802.11i – Has been implemented in products such as

WPA2 WPA2 has newer, more robust security protocols

based on the Advanced Encryption Standard

– WPA /WPA 2 provide increased capabilities for authentication, encryption, and throughput

Managing Wireless Connections

• Regulate the wireless network footprint

• Select WPA or WPA2 over WEP

• Protect preshared keys

Wi-Fi security

SSID should be a non-default value SSID broadcast should be disabled MAC access control Authentication

Require ID and password, may use a RADIUS server

Encryption WEP (Wired Equivalent Privacy) WPA (Wireless Protected Access) WPA2 (superset of WPA, full standard

PSK v. RADIUS

WPA and WPA-2 operate in two modes Pre-Shared Key (PSK)

Users must enter the key on each device RADIUS server

Used with 802.1x authentication Each user has an individual key More secure, recommended for enterprises

Scanning and Analysis Tools

• Used to find vulnerabilities in systems

• Security administrators may use attacker’s tools to examine their own defenses and search out areas of vulnerability

• Scanning tools • Footprinting• Fingerprinting

Port Scanners

• Port scanning utilities (port scanners)

Vulnerability Scanners

• Capable of scanning networks for very detailed information

• Identify exposed user names and groups, show open network shares, and expose configuration problems and other server vulnerabilities

http://www.tenable.com/products/nessus

Packet Sniffers

• A network tool that collects and analyzes packets on a network

• Connects directly to a local network from an internal location

http://www.wireshark.org/

Content Filters

• A software program or a hardware/software appliance that allows administrators to restrict content that comes into a network

• Common application of a content filter– Restriction of access to Web sites with non-

business-related material, such as pornography, or restriction of spam e-mail

Examples of Content Filters

Trap and Trace

• Trap– Describes software designed to entice

individuals who are illegally perusing the internal areas of a network

• Trace– A process by which the organization attempts

to determine the identity of someone discovered in unauthorized areas of the network or systems

Managing Scanning and Analysis Tools• The security manager must be able to see

the organization’s systems and networks from the viewpoint of potential attackers

Managing Scanning and Analysis Tools (cont’d.)• Drawbacks:

– Tools do not have human-level capabilities– Most tools function by pattern recognition, so

they only handle known issues – Most tools are computer-based, so they are

prone to errors, flaws, and vulnerabilities of their own

– Tools are designed, configured, and operated by humans and are subject to human errors

Managing Scanning and Analysis Tools (cont’d.)• Drawbacks: (cont’d.)

– Some governments, agencies, institutions, and universities have established policies or laws that protect the individual user’s right to access content

– Tool usage and configuration must comply with an explicitly articulated policy, and the policy must provide for valid exceptions