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Lecture 19 Hacking 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. 2 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 EXELLENT SOFTWARE CAN PROVIDE YOU BEST SECURITY  LIKE • TROJAN • FIREWALL TROJAN  WINDOWS TROJANS ARE SMALL ASPECT OF WINDOWS SECURUTY  TROJAN IS UNOTHORIZED PROGRAM CONTAINED WITHIN A LEGIMATE 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 • PACKET FILTER • APPLICATION PROXY • PACKET INSPECTION 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 7 Common Steps for Attackers • Scanning – Identifying systems that are running and services that are active on them – Examples: Ping sweeps and port scans 8 Common Steps for Attackers • Gaining Access – Exploiting identified vulnerabilities to gain unauthorized access – Examples: Exploiting a buffer overflow or brute forcing a password and logging onto a system 9 Common Steps for Attackers • Maintaining Access – Uploading malicious software to ensure re-entry is possible – Example: Installing a backdoor on a system 10