Lecture 19Hacking

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.

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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

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Common Steps for Attackers

• Scanning– Identifying systems that are running and services

that are active on them– Examples: Ping sweeps and port scans

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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

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Common Steps for Attackers

• Maintaining Access– Uploading malicious software to ensure re-entry is

possible– Example: Installing a backdoor on a system

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Common Steps for Attackers

• Covering Tracks– Carrying out activities to hide one’s malicious

activities– Example: Deleting or modifying data in a system

and its application logs

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