Ethical Hacking and Countermeasures: Attack Phases, Second Edition. Chapter 1 Introduction to Ethical Hacking

Transcription

1 Ethical Hacking and Countermeasures: Attack Phases, Second Edition Chapter 1 Introduction to Ethical Hacking

2 Objectives After completing this chapter, you should be able to: Understand the importance of information security in today s world Understand the elements of security Identify the phases of the hacking cycle Identify the different types of hacker attacks Understand hacktivism 2

3 Objectives After completing this chapter, you should be able to (cont d): Understand ethical hacking Understand vulnerability research and identify tools assisting in vulnerability research Identify steps for conducting ethical hacking Understand computer crimes and implications 3

4 Introduction to Ethical Hacking Hackers have various motivations for breaking into secure systems Duty of system administrators and network security professionals To guard their infrastructure against exploits by knowing the enemies who seek to use the same infrastructure for their own purposes One of the best ways to do this is to hire an ethical hacker Someone who has all of the skills of a malicious hacker, but is on the client s side 4

5 Importance of Security Today, companies are completely networked, exchanging information almost instantly Of utmost importance to secure assets from outside threats Security policy Specification for how objects in a security domain are allowed to interact There is an increased dependency on computers Any disruption in their operation or integrity can mean the loss of time, the loss of money, and sometimes even the loss of life 5

6 Threats and Vulnerabilities Vulnerability Weakness in a defined asset that could be taken advantage of or exploited by some threat Threat Action or event that might compromise security Every vulnerability does not lead to an attack, and all attacks do not result in success Factors that result in the success of an attack Degree of vulnerability, the strength of the attack, and the extent to which countermeasures are adopted 6

7 Attacks Target of evaluation Information resource or asset that is being protected from attacks Attack Deliberate assault on that system s security Attacks can be classified as Active modify the target system Passive violate the confidentiality of a system s data without affecting the state of that system Example: electronic eavesdropping 7

8 Attacks Attacks can also be categorized as inside or outside attacks Inside initiated from within a network by an authorized user Outside caused by an external intruder who does not have authorization to access the network 8

9 Security Breaches Exploit A specific way to breach the security of an IT system through a vulnerability Exposure A breach in security Can vary from one company to another, or even from one department to another Imperative for organizations to address both penetration and protection issues 9

10 Exposure Exposure Loss due to an exploit Examples of loss include Disclosure, deception, disruption, and usurpation Vulnerability is the primary entry point an attacker can use to gain access to a system or to its data Once the system is exposed, an attacker can collect confidential information with relative ease, and usually erase his or her tracks afterwards 10

11 Elements of Security Security: the state of well-being of a system s data and infrastructure Assurance Confidence that the system will behave according to its specifications 11

12 Accountability Accountability System administrators or concerned authorities need to be able to know by whom, when, how and why system resources have been accessed An audit trail or log files can address this 12

13 Reusability Reusability Generally, not all resources are available to all users Having access controls on predefined parameters can help increase the level of security One user or program may not reuse or manipulate objects that another user or program is currently accessing in order to prevent violation of security Also known as availability 13

14 The Security, Functionality, and Ease of Use Triangle Figure 1-1 Moving toward security means moving away from functionality and ease of use 14

15 The Growth of Hacking Originally, hacking required extraordinary computer skills Today there are automated tools and codes available on the Internet that make it possible for almost anyone to successfully hack a system A victim will often keep the attack secret For fear of losing the goodwill and faith of employees, customers, and partners Critical to take countermeasures to prevent any exploits that can result in loss 15

16 Phases of an Attack In general, there are five phases that make up an attack: 1. Reconnaissance 2. Scanning 3. Gaining access 4. Maintaining access 5. Covering tracks 16

17 Phase 1 - Reconnaissance Reconnaissance Preparatory phase where an attacker gathers as much information as possible about the target prior to launching the attack Reconnaissance may involve social engineering Convincing other people to reveal information such as unlisted phone numbers, passwords, etc. Dumpster diving Looking through an organization s trash for any discarded sensitive information 17

18 Phase 1 - Reconnaissance Reconnaissance types Passive: attacker does not interact with the system directly Active: attacker interacts with the target system by using tools to detect open ports, accessible hosts, router locations, network mapping, details of operating systems, and applications An ethical hacker must be able to distinguish among various reconnaissance methods Advocate preventative measures 18

19 Phase 2 - Scanning Attacker uses the details gathered during reconnaissance to identify specific vulnerabilities An attacker can gather critical network information, such as the mapping of systems, routers, and firewalls By using simple tools such as the Windows utility Traceroute Port scanners can be used to detect listening ports to find information about the nature of services running on the target machine Vulnerability scanners: most commonly used tools 19

20 Phase 3 Gaining Access Gaining access Where most of the damage is usually done, yet hackers can cause damage without gaining any access to the system Access can be gained locally, offline, over a LAN, or over the Internet Spoofing Technique used to exploit the system be pretending to be a legitimate user 20

21 Phase 3 Gaining Access Smurf attacks Attempt to cause users on a network to flood each other with data, making it appear as if everyone is attacking each other A hacker s chances of gaining access into a target system are influenced by factors such as: Architecture and configuration of the target system Skill level of the perpetrator Initial level of access obtained 21

22 Phase 4 Maintaining Access Attackers, who choose to remain undetected Remove evidence of their entry Install a backdoor or a Trojan to gain repeat access Install rootkits at the kernel level to gain full administrator access to the target compute Hackers can use Trojans to transfer user names, passwords, and any other information stored on the system Organizations can use intrusion detection systems or deploy traps known as honeypots and honeynets to detect intruders 22

23 Phase 5 Covering Tracks Attackers will usually attempt to erase all evidence of their actions Trojans such as ps or netcat are often used to erase the attacker s activities from the system s log files Steganography Process of hiding data in other data, for instance image and sound files Tunneling Takes advantage of the transmission protocol by carrying one protocol over another 23

24 Phase 5 Covering Tracks System administrators can deploy host-based IDS (intrusion detection systems) In order to detect Trojans and compromised files and directories As an ethical hacker You must be aware of tools and techniques that attackers deploy in order to advocate and implement countermeasures 24

25 Types of Hacker Attacks Hacker attacks can be categorized as: Operating system attacks Application-level attacks Shrink-wrap code attacks Misconfiguration attacks 25

26 Operating System Attacks Today s operating systems contain many features, making them increasingly complex Keeping up with latest patches and hotfixes can be challenging with today s complex networks Attackers are constantly looking for OS vulnerabilities to exploit 26

27 Application-Level Attacks Software developers often do not have time to completely test their products before shipping them Leaving undiscovered security holes Security is frequently delivered as an add-on component after release Not all instances of the software will have the same level of security Error checking can be very poor Which leads to buffer overflow attacks 27

28 Shrink-Wrap Code Attacks Software developers will often use free libraries and code licensed from other sources in their programs If vulnerabilities in that code are discovered, many pieces of software are at risk Developers need to customize and fine-tune code in order to make it more secure And different enough that the same exploit will not work 28

29 Misconfiguration Attacks System administrators need to be careful when configuring systems Create a simple, but usable configuration Remove all unnecessary services and software 29

30 Hacktivism Hacktivism When hackers break into government or corporate computer systems as an act of protest Use it to increase awareness of their social or political agendas Considered a crime, irrespective of intentions 30

31 Hacker Classes Black hats Use skills for illegal or malicious purposes White hats Use skills for defensive purposes Gray hats Believe in full disclosure (information is better out in the open than kept in secret) Suicide hackers Hacktivists who are willing to become martyrs for their cause 31

32 Ethical Hackers Ethical hackers Information security professionals who specialize in evaluating and defending against threats from attackers Use excellent computer skills to protect the integrity of computer systems rather than hurting them Ethical hackers categories: Former black hats White hats Consulting firms 32

33 What Do Ethical Hackers Do? Ethical hacker s evaluation of a client s information system security seeks answers to three basic questions: 1. What can an attacker see on the target system? 2. What can an intruder do with that information? 3. Are the attackers attempts being noticed on the target systems? Ethical hacker must convey to the client that it is never possible to guard systems completely However, they can always be improved 33

34 Can Hacking Be Ethical? Today, the term hacking is closely associated with illegal and unethical activities Most companies use IT professionals to audit their systems for known vulnerabilities Ethical hackers usually employ the same tools and techniques as attackers With the exception that once access is gained, no damage is done Distinction between ethical hackers and crackers is consent Crackers attempt to gain unauthorized access 34

35 Skills of an Ethical Hacker Ethical hackers must be computer experts Must have a strong grasp on programming and networking Should be comfortable with installing and maintaining systems using all popular OSs Ethical hackers must possess detailed knowledge of both hardware and software Any ethical hacker must have plenty of patience Analysis stage consumes more time than the testing stage 35

36 What is Vulnerability Research? Vulnerability research includes: Discovering system design faults and weaknesses that might allow attackers to compromise a system Keeping informed of new products and technologies in order to find news related to current exploits Checking underground hacking Web sites for newly discovered vulnerabilities and exploits Checking newly released alerts regarding relevant innovations and product improvements for security systems 36

37 Why Hackers Need Vulnerability Reasons: Research? To identify and correct network vulnerabilities To protect the network from being attacked To get information that helps to prevent security issues To gather information about viruses and malware To find weaknesses in the network and to alert the network administrator before a network attack To know how to recover from a network attack 37

38 Vulnerability Research Web Sites Vulnerability research web sites include: US-CERT ( National Vulnerability Database ( Securitytracker ( SecuriTeam ( SecurityFocus ( SCMagazine ( 38

39 Conducting Ethical Hacking Each ethical hacking assignment has six basic steps: 1. Talk with the client about the importance of security and the necessity of testing 2. Prepare NDA (nondisclosure agreement) documents and have the client sign them 3. Prepare an ethical hacking team and create a schedule for testing 4. Conduct the test 5. Analyze the results and prepare the report 6. Deliver the report to the client 39

40 How Do They Go About It? Security testing involves three phases: preparation, conduct, and conclusion After discussing security issues with the client, a formal contract should be drawn up that contains NDA, to protect the client s confidential data Clause stating that the ethical hacker has full consent of the client to hack into their systems Conduct phase Two most common approaches: Limited vulnerability analysis Attack and penetration testing 40

41 How Do They Go About It? The needs of the client Clients will often prefer a limited vulnerability analysis because they do not want to lose any data or risk any unintended damage While conducting an evaluation, ethical hackers may come across security holes that cannot be fixed within the predetermined time frame Client should be warned of this Final phase is the conclusion phase A report is prepared for the client 41

42 Approaches to Ethical Hacking Ethical hacker will attempt attacks over various channels: Remote network Remote dial-up network Local network Stolen equipment Social engineering Physical entry 42

43 Ethical Hacking Testing Approaches fall into one of three categories: Black box testing Ethical hacker is given no prior knowledge or information about a system White box testing Ethical hacker is given full advance knowledge of the system Gray box testing Internal testing performed by system administrator and network professionals 43

44 Ethical Hacking Deliverables In the conclusion phase, the ethical hacker creates a detailed report for the client Analyzing the possibility and impact of hacking Vulnerabilities that were detected are explained in detail Along with specific recommendations to patch them in order to bring about a permanent security solution Client may also solicit the participation of its employees by asking them for suggestions or observations during the course of the evaluation Final report should be delivered only in a hard copy 44

45 Computer Crimes and Implications Computer crimes can be separated into two categories: Crimes facilitated by use of a computer Crimes where the computer is the target The Cyber Security Enhancement Act 2002 allows life sentences for hackers who recklessly endanger the lives of others For more information, visit the United States Department of Justice s Cyber Crime and Intellectual Property section at 45

46 Summary The importance of security in any network is often underestimated Ethical hacking simulates a malicious attack without trying to cause damage Hacking involves five distinct phases: reconnaissance, scanning, gaining access, maintaining access, and clearing tracks Vulnerability research can be done via several Web sites 46

47 Summary Security testing involves three phases preparation, conduct, and conclusion Cyber crime is underreported, but taken very seriously when it is 47