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Professional Practices in Information Technology CSC 110 ProfessionalPracticesi n Information Technology HandBook COMSATS Institute of Information Technology (Virtual Campus) Islamabad, Pakistan Professional Practices in Information Technology CSC 110 Lecture 19 Introduction to Hacking 19.1 What Is Network Security? Security is much larger than just packets, firewalls, and hackers. Security includes: – Policies and procedures – Liabilities and laws – Human behavior patterns – Corporate security programs and implementation – Technical aspects- firewalls, intrusion detection systems, proxies, encryption, antivirus software, hacks, cracks, and attacks Understanding hacking tools and how attacks are carried out is only one piece of the puzzle.  Attacks There are many types of attacks – Spoofing attack – Telnet based attack – DOS (Daniel of service) attack – Ping of death – Distributed dos attack – Mailbombs  Need For Security Some excellent software can provide you best security, like: – Trojan – Firewall Professional Practices in Information Technology CSC 110  Trojan Windows Trojans are small aspect of windows security. Trojan is unauthorized program contained within a legitimate program. This program performs function unknown by user.  Firewall Firewall is any device used to prevent outsiders from gaining access to your network. Types of firewalls are: – Packet filter – Application proxy – Packet inspection 19.2 Common Steps for Attackers Reconnaissance – Intelligent work of obtaining information either actively or passively – Examples: • Passively: Sniffing Traffic, eavesdropping • Actively: Obtaining data from American Registry for Internet Numbers (ARIN), whois databases, web sites, social engineering Scanning – Identifying systems that are running and services that are active on them – Examples: Ping sweeps and port scans Gaining Access – Exploiting identified vulnerabilities to gain unauthorized access – Examples: Exploiting a buffer overflow or brute forcing a password and logging onto a system Maintaining Access – Uploading malicious software to ensure re-entry is possible – Example: Installing a backdoor on a system Covering Tracks Professional Practices in Information Technology CSC 110 – Carrying out activities to hide one’s malicious activities – Example: Deleting or modifying data in a system and its application logs 19.3 Where do Attackers get the Most Traction? Flaws within software are the root of the problem of successful attacks and exploits. Security does not like complexity. The more complex software gets, the harder it is to properly predict how it will react in all possible scenarios thus making it much harder to secure. Windows XP is approximately 40 million lines of code. Linux is approximately 2 million lines of code. Estimate in industry: 5 to 10 bugs per 1,000 lines of code => Windows XP has approximately 200,000 bugs. With object-oriented language applications and operating systems using each other’s code, DLLs are installed and shared, many applications communicate with each other => Operating Systems cannot control this flow and provide protection against possible compromises  Enough Blame to Go Around Software vendors do not consider security in the design and specification phases. Programmers have not been properly taught how to code securely. Vendors are not held liable for faulty code. Consumers are not willing to pay more for properly developed and tested code.  Novice versus Advanced Novice ethical hacker will use tools/techniques developed by others. A more advanced ethical hacker will not only depend upon other people’s tools but will have the skill set and understanding to develop their own tools/techniques.