Podcast
Questions and Answers
Which of the following languages is NOT mentioned as part of the web security resources?
Which of the following languages is NOT mentioned as part of the web security resources?
Web security only concerns static content and does not involve dynamic content.
Web security only concerns static content and does not involve dynamic content.
False
What middleware is frequently used to analyze URLs and compose web pages for Apache and MySQL?
What middleware is frequently used to analyze URLs and compose web pages for Apache and MySQL?
PHP scripts
The _____ attack involves exploiting vulnerabilities in web applications through client-side scripts.
The _____ attack involves exploiting vulnerabilities in web applications through client-side scripts.
Signup and view all the answers
Match the following web security terms with their descriptions:
Match the following web security terms with their descriptions:
Signup and view all the answers
What is typically required for a web server to create dynamic content?
What is typically required for a web server to create dynamic content?
Signup and view all the answers
Cookies can be utilized by attackers in XSS attacks to steal user information.
Cookies can be utilized by attackers in XSS attacks to steal user information.
Signup and view all the answers
What is the first step to execute the CGI script WealthTracker.cgi?
What is the first step to execute the CGI script WealthTracker.cgi?
Signup and view all the answers
The WealthTracker.html file is supposed to send data back to the server.
The WealthTracker.html file is supposed to send data back to the server.
Signup and view all the answers
What does the command 'var cookie_info = document.cookie' do?
What does the command 'var cookie_info = document.cookie' do?
Signup and view all the answers
Heap spraying fills up memory with _____ bytes referred to as nop-sled.
Heap spraying fills up memory with _____ bytes referred to as nop-sled.
Signup and view all the answers
Match the following steps of the Heap Spray Exploit with their descriptions:
Match the following steps of the Heap Spray Exploit with their descriptions:
Signup and view all the answers
What could potentially allow malicious attacks on a server when a user submits their credentials?
What could potentially allow malicious attacks on a server when a user submits their credentials?
Signup and view all the answers
SQL injection attacks can only occur when input fields are not properly validated.
SQL injection attacks can only occur when input fields are not properly validated.
Signup and view all the answers
What is the purpose of the PHP package 'php7.0-mysql'?
What is the purpose of the PHP package 'php7.0-mysql'?
Signup and view all the answers
The MySQL database used in the example is named __________.
The MySQL database used in the example is named __________.
Signup and view all the answers
Match the following terms with their descriptions:
Match the following terms with their descriptions:
Signup and view all the answers
How many accounts are created in the MySQL database for user access?
How many accounts are created in the MySQL database for user access?
Signup and view all the answers
The presence of 'localhost.localdomain' in an email header can indicate it originated from a residential IP block.
The presence of 'localhost.localdomain' in an email header can indicate it originated from a residential IP block.
Signup and view all the answers
What action does the visitor take after filling out the form in RetrieveFromMySQL.html?
What action does the visitor take after filling out the form in RetrieveFromMySQL.html?
Signup and view all the answers
When accessing the Maintenance_Schedule table, users can only view __________.
When accessing the Maintenance_Schedule table, users can only view __________.
Signup and view all the answers
What type of web server works with the MySQL database in the mentioned example?
What type of web server works with the MySQL database in the mentioned example?
Signup and view all the answers
What is the primary goal of the XSS attack with server-side injection described?
What is the primary goal of the XSS attack with server-side injection described?
Signup and view all the answers
The injected PHP code will be visible to clients when they view the page source in their browser.
The injected PHP code will be visible to clients when they view the page source in their browser.
Signup and view all the answers
What is the IP address of the Web Hosting Service Provider?
What is the IP address of the Web Hosting Service Provider?
Signup and view all the answers
The service that handles sending emails on the server is called ______.
The service that handles sending emails on the server is called ______.
Signup and view all the answers
Match the following entities with their associated IP addresses:
Match the following entities with their associated IP addresses:
Signup and view all the answers
Which of the following operating systems does the web hosting service provider use?
Which of the following operating systems does the web hosting service provider use?
Signup and view all the answers
The innocent client's web browser is Internet Explorer.
The innocent client's web browser is Internet Explorer.
Signup and view all the answers
What file is created by the uploadfile.php script?
What file is created by the uploadfile.php script?
Signup and view all the answers
The upload page provided to clients is called ______.
The upload page provided to clients is called ______.
Signup and view all the answers
What is a major enabler of SQL injection exploits?
What is a major enabler of SQL injection exploits?
Signup and view all the answers
SQL injection can enable a user to delete all tables in a database.
SQL injection can enable a user to delete all tables in a database.
Signup and view all the answers
What does PDO stand for in the context of database security?
What does PDO stand for in the context of database security?
Signup and view all the answers
The Slowloris Attack can potentially bring down a web server due to insufficient _____ available to it.
The Slowloris Attack can potentially bring down a web server due to insufficient _____ available to it.
Signup and view all the answers
Match the following SQL concepts with their descriptions:
Match the following SQL concepts with their descriptions:
Signup and view all the answers
What command can a user input to potentially delete all tables in the database?
What command can a user input to potentially delete all tables in the database?
Signup and view all the answers
A Slowloris attack sends complete requests to a web server.
A Slowloris attack sends complete requests to a web server.
Signup and view all the answers
Who authored the Slowloris attack?
Who authored the Slowloris attack?
Signup and view all the answers
A TCP connection established during a Slowloris attack is kept open until it _____ .
A TCP connection established during a Slowloris attack is kept open until it _____ .
Signup and view all the answers
What is the main reason SQL Injection exploits are successful?
What is the main reason SQL Injection exploits are successful?
Signup and view all the answers
Study Notes
Lecture 08: Web Security
- The lecture focuses on web security, covering issues relevant to web servers, browsers, and user interactions.
- Prerequisites for the lecture include URL, HTTP, and HTML knowledge.
- Software like Apache2 web server, PHP7, MySQL, and sendmail are required.
- Programming languages such as PHP, Perl, Python, JavaScript, and CGI scripts are used in web development.
- Resources for further study include PHP comparisons, manuals, tutorials, MySQL documentation, PDO tutorials, Modsecurity projects, JavaScript tutorials, and OWASP resources for application security.
- Topics outlined include XSS attacks (server-side injection), SQL injection attacks, Slowloris attacks, mod-security, client-side XSS, cookie theft using XSS, and heap spray exploits.
Prerequisites
- URL, HTTP, and HTML knowledge are needed.
- Apache2 web server installed on an Ubuntu machine.
- Apache2 server is enabled with PHP7.
- MySQL database management system used as database backend.
- A driver to enable PHP communication with MySQL.
- Sendmail program running on the server.
Languages
- PHP
- Perl
- MySQL
- Python
- JavaScript
- CGI scripts
Resources
- PHP vs. NodeJS comparison and benchmarks (2018)
- PHP Manual
- PHP Tutorial
- MySQL Documentation
- PDO tutorials (addressing PHP delusions)
- Modsecurity Project
- JavaScript Tutorial
- OWASP Foundation (Open Source Foundation for Application Security)
Outline
- XSS attack with server-side injection
- SQL Injection Attack
- Slowloris Attack
- mod-security
- Client-side XSS
- Cookies and XSS for stealing cookies
- Heap Spray Exploit
Web Security
- Web security addresses issues specific to how web servers display content to browsers, how browsers interact with servers, and how users interact with browsers.
- The World Wide Web, web servers initially offered only static content.
- Now, dynamic content is common, often tied to a database server.
- Middleware (often PHP scripts) is frequently used for this purpose, particularly with Apache and MySQL.
XSS Attack with Server-Side Injection
- This type of attack injects malicious code, often PHP, during upload processes.
- The injected code isn't visible in the browser's source.
- The goal might be to download a spam file from a third-party source as soon as the page loads.
- A diagram illustrates the attack flow, showing the attacker's web hosting provider injecting the script into the web pages uploaded by users.
XSS Attack with Server-Side Injection (Details)
- Specific details are provided about the web servers, clients, and email providers involved.
- Example code snippets showing the injected PHP code demonstrate how the attack works.
SQL Injection Attack
- PHP and MySQL work together to manage web server databases. The "php7.0-mysql" package allows for direct database connections via a PHP Data Objects (PDO) based driver.
- A MySQL database (Manager_db) with user accounts (Operator1, Operator2, Operator3) and a Maintenance_Schedule table are setup for illustration.
- The initial table setup shows each operator's schedules relating to specific equipment.
SQL Injection Attack (Details)
- An attacker could insert malicious code to modify or delete data (delete all tables) in the database.
- An important factor is that the SQL syntax places commands and data on equal footing.
Security against SQL Injection
- To prevent this, user inputs need careful filtering and restricted command access.
- PDO (PHP Data Objects) based drivers offer consistent API usage across diverse database systems. They often include built-in security measures against SQL Injection.
Kak's Code (Lecture 27)
- Specific file names (RetrieveFromMySQL.html, RetrieveFromMySQL.php) are listed for code.
The Slowloris Attack
- Developed by Robert Hansen in 2009.
- The attack involves sending incomplete HTTP requests to a web server.
- This keeps many TCP connections open, overwhelming the server's capacity.
The Slowloris Attack: Example 1, 2, and 3
- Illustrations of client-side scripts (ClientSocketFetchDocs.py, TestHTTPServerWithNoCRLF.py) and server-side scripts (CheckNetstat.sh, RepeatedAttack.sh, TerminateLoris.sh) used in the attack demonstrate the attack's method.
SlowPost Attack
- Similar to Slowloris but uses POST requests instead of GET requests.
Kak's Code (Lecture 28)
- Specific file names (WealthTracker.html) for the relevant code are listed.
XSS for Stealing Cookies
-
Third parties can steal cookies via XSS attacks. JavaScript is used in these attacks.
-
Example steps for a cookie-stealing attack are given, showing how to bring up the JavaScript console, and the required commands are illustrated to steal cookies.
-
The web server named 'Collector.cgi' is part of the attack and stores stolen cookies.
The Heap Spray Exploit
- This exploit uses JavaScript to execute shell commands by exploiting how script engines manage memory.
Heap Spray References
- References to documentation on the heap spray technique are provided.
Web Vulnerabilities
- Historical security issues with browsers' interactions with servers (e.g., Samy worm).
Browser Vulnerabilities
- Vulnerabilities like JavaScript and the DOM (Document Object Model) are discussed.
- Another common technique (e.g. using <iframe>) is addressed, as well as the potential for another web page to be embedded within the target page.
Web Application Security
- The OWASP (Open Web Application Security Project) is mentioned as a notable resource.
- Tools like W3af for testing web applications for vulnerabilities (SQL injection, cross-site scripting, remote file inclusion) are discussed.
Reference
- A PDF file reference (for subverting AJAX) is listed.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on web security concepts, including dynamic content, common attacks, and functionalities of web servers. This quiz covers various critical topics about safeguarding web applications and understanding vulnerabilities. Challenge yourself with matching terms and answering specific questions!
