< Back to catalog

Web application security in C#

CELCsWeb
AI narration
Online VM (Linux)
C#
Developer
e-Learning
Pricing Inquiry Download PDF

Base training

labs

48 Labs

case_study

29 Case Studies

Monthly feed

A combination of repeated and new skills & drills for continuous learning

labs

2-3 labs

case_study

Case study

Platform

Web

Audience

C# developers working on Web applications

Preparedness

General C# and Web development

Standards and references

OWASP, CWE and Fortify Taxonomy

Outline

  • Cyber security basics
  • The OWASP Top Ten
  • A01 - Broken Access Control
  • A02 - Security Misconfiguration
  • A03 - Software Supply Chain Failures
  • A04 - Cryptographic Failures
  • A05 - Injection
  • A06 - Insecure Design
  • A07 - Authentication Failures
  • A08 - Software or Data Integrity Failures
  • A09 - Logging and Alerting Failures
  • A10 - Mishandling of Exceptional Conditions
  • X02 - Memory Management Failures
  • Wrap up

What you will learn

  • Getting familiar with essential cyber security concepts
  • Identify Web application vulnerabilities and their consequences
  • Learn the security best practices in C#
  • Input validation approaches and principles
  • Understanding Web application security issues
  • Detailed analysis of the OWASP Top Ten elements
  • Putting Web application security in the context of C#
  • Going beyond the low hanging fruits

Description

The course provides a comprehensive exploration of secure coding principles and practices tailored specifically for C# developers. Starting off from the foundations of cybersecurity, you will understand the consequences of insecure code by examining threats through the lens of the CIA triad.

In the main part of the material, you will systematically walk through the various vulnerabilities outlined in the OWASP Top Ten. As you progress through the modules investigating the intricacies of authentication and authorization, through realizing the practical aspects of cryptography, to tackling injection attacks, you will gain a deep understanding of both theoretical concepts and practical skills for securing C# web applications. Further subjects are aligned to some common software security weakness types, such as error handling, code quality or denial of service.

These modules go beyond just the theory. Not only do they identify vulnerabilities, show their consequences, and detail the best practices, but – through hands-on labs and real-world case studies – they offer practical experience in identifying, exploiting, and mitigating these security risks within C#-based web applications.

So that you are prepared for the forces of the dark side.

So that nothing unexpected happens in your code.

Nothing.

Note:

Note: This course content is available as an e-learning subscription. We reserve a period of 3 months to digest the foundational material, after which we activate shorter learning units on a monthly basis. This gives secure coding efforts an initial boost, and builds up sustained readiness over time. These learning units are indicated in red in the table of contents below.

Table of contents

  • Authorization
    • Access control basics
    • Access control types
    • Case study – Broken authz in FIFA platform during 2026 World Cup
    • Confused deputy
  • Insecure Direct Object Reference
    • Insecure direct object reference (IDOR)
    • Path traversal
    • Lab – Insecure Direct Object Reference
    • Path traversal best practices
  • Horizontal authorization
    • Authorization bypass through user-controlled keys
    • Case study – Remote takeover of Nexx garage doors and alarms
    • Lab – Horizontal authorization
  • File upload
    • Unrestricted file upload
    • Good practices
    • Lab – Unrestricted file upload
    • Case study – File upload vulnerability in Citrix ShareFile
  • Cross-site Request Forgery (CSRF)
    • Lab – Cross-site Request Forgery
  • Cross-site Request Forgery (CSRF) best practices
    • CSRF best practices
    • CSRF defense in depth
    • CSRF (XSRF) protection in Angular
    • Lab – CSRF protection with tokens
  • SSRF
    • Server-side Request Forgery (SSRF)
    • Case study – SSRF and the Capital One breach
  • Misconfiguration and XML parsing
    • Configuration principles
    • XML Entities
    • DTD and the entities
    • Entity expansion
  • XML External Entity (XXE)
    • File inclusion with external entities
    • Server-Side Request Forgery with external entities
    • Lab – External entity attack
    • Case study – XXE vulnerability in SharePoint
  • XXE best practices
    • Preventing XXE
    • Lab – Prohibiting DTD
  • Web security configuration issues
    • Content Security Policy
    • Resource control
    • Fetch directives
    • Source allowlisting
    • Strict CSP: using nonces and hashes
    • Navigation and reporting directives
    • Document restrictions and sandboxing
    • Browser support
    • CSP best practices
    • Cookie attributes
  • Secrets management
    • Hard coded passwords
    • Best practices
    • Lab – Hardcoded password
  • Vulnerable components and dependencies
    • Using vulnerable components
    • Assessing the environment
    • Hardening
    • Untrusted functionality import
    • Supply chain security and the Software Bill of Materials (SBOM)
    • SBOM examples
    • Case study – The Polyfill.io supply chain attack
  • Vulnerability management
    • Patch management
    • Vulnerability databases
    • Vulnerability rating – CVSS
    • Lab – Finding vulnerabilities in third-party components
    • Bug bounty programs
  • Build security
  • Dangerous and obsolete language elements
    • Using dangerous language elements
    • Using obsolete language elements
  • Information exposure
    • Exposure through extracted data and aggregation
    • Case study – Strava data exposure
    • Leaking system information
  • Cryptography for developers
    • Cryptography basics
    • Crypto APIs in C#
  • Hashing
    • Hashing basics
    • Hashing in C#
    • Lab – Hashing in C#
  • PRNG
    • Random number generation
    • Pseudo random number generators (PRNGs)
    • Cryptographically secure PRNGs
    • Using virtual random streams
    • Case study – Equifax credit account freeze
  • PRNG in C#
    • Weak PRNGs
    • Using random numbers in C#
    • Lab – Using random numbers in C#
  • Encryption
    • Confidentiality protection
    • Symmetric encryption
    • Block ciphers
    • Modes of operation
    • Modes of operation and IV – best practices
  • Encryption in C#
    • Symmetric encryption in C#
    • Symmetric encryption in C# with streams
    • Lab – Symmetric encryption in C#
    • Case study – Padding oracle used in RCE against Citrix ShareFile
  • Asymmetric encryption
    • The RSA algorithm
    • Using RSA – best practices
    • RSA in C#
    • Case study – RSA attacks: Bleichenbacher, ROBOT, and Marvin
    • Combining symmetric and asymmetric algorithms
  • Key exchange and agreement
    • Key exchange
    • Diffie-Hellman key agreement algorithm
    • Key exchange pitfalls and best practices
  • Injection problems
    • Injection principles
    • Injection attacks
  • SQL injection
    • SQL injection basics
    • Lab – SQL injection
  • SQL injection attack techniques
    • Attack techniques
    • Content-based blind SQL injection
    • Time-based blind SQL injection
  • SQL injection best practices
    • Input validation
    • Parameterized queries
    • Lab – Using prepared statements
  • SQL injection additional considerations
    • Database defense in depth
    • Case study – SQL injection leading to RCE in Ivanti Endpoint Manager
  • Beyond SQL injection – ORM and NoSQL
    • SQL injection protection and ORM
    • Entity Framework and SQL injection
    • NoSQL injection basics
  • Code injection
    • OS command injection
    • Lab – Command injection
  • OS command injection best practices
    • Avoiding command injection with the right APIs
    • Lab – Command injection best practices
    • Case study – Shellshock
    • Lab – Shellshock
    • Case study – Command injection in Ruckus
  • HTML injection – Cross-site scripting (XSS)
    • Cross-site scripting basics
    • Persistent cross-site scripting
    • Reflected cross-site scripting
    • Client-side (DOM-based) cross-site scripting
  • XSS attacks
    • Lab – Stored XSS
    • Lab – Reflected XSS
    • Case study – XSS to RCE in Azure Service Fabric
  • XSS best practices 1
    • Protection principles – escaping
    • XSS protection APIs
    • Lab – XSS fix / stored
  • XSS best practices 2
    • Further XSS protection techniques
    • Lab – XSS fix / reflected
    • Additional protection layers – defense in depth
    • XSS protection in Angular
    • XSS protection in React
  • Advanced XSS
    • Additional XSS exploitation and protection
    • Lab – Stored XSS in attribute
    • Lab – XSS fix / stored (in HTML attributes)
    • Client-side protection principles
  • Template injection
    • Script injection
    • Server-side template injection (SSTI)
    • Client-side template injection (CSTI) in Angular
    • Client-side template injection (CSTI) in React
  • Input validation principles 1
    • Input validation principles
    • Denylists and allowlists
    • Data validation techniques
    • Lab – Input validation
  • Input validation principles 2
    • What to validate – the attack surface
    • Where to validate – defense in depth
    • When to validate – validation vs transformations
  • Input validation principles 3
    • Output sanitization
    • Encoding challenges
    • Unicode challenges
    • Lab – Encoding challenges
    • Lab – Dealing with Unicode homoglyph attacks
    • Validation with regex
  • Path traversal and file validation
    • Path traversal
    • Lab – Path traversal
    • Path traversal-related examples
    • Additional challenges in Windows
    • Case study – File spoofing in WinRAR
    • Virtual resources
    • Path traversal best practices
    • Lab – Path canonicalization
  • Unsafe reflection
    • Reflection without validation
    • Lab – Unsafe reflection
    • Are accessibility modifiers a security feature?
    • Accessibility modifiers – best practices
  • Unsafe native code
    • Native code dependence
    • Lab – Unsafe native code
    • Best practices for dealing with native code
  • Insecure design
    • The STRIDE model of threats
    • Secure design principles of Saltzer and Schroeder
  • Insecure design – Saltzer and Schroeder 1
    • Economy of mechanism
    • Fail-safe defaults
    • Complete mediation
    • Open design
  • Insecure design – Saltzer and Schroeder 2
    • Separation of privilege
    • Least privilege
    • Least common mechanism
    • Psychological acceptability
  • Client-side security
    • Same Origin Policy
    • Simple request
    • Preflight request
    • Cross-Origin Resource Sharing (CORS)
  • Clickjacking
    • Frame sandboxing
    • Cross-Frame Scripting (XFS) attacks
    • Lab – Clickjacking
    • Clickjacking beyond hijacking a click
  • Anti-clickjacking best practices
    • Clickjacking protection best practices
    • Lab – Using CSP to prevent clickjacking
  • Authentication
    • Authentication basics
    • Multi-factor authentication (MFA)
    • Case study – The InfinityGauntlet attack
    • Authentication weaknesses
  • Session security
    • Session management essentials
    • Why do we protect session IDs – Session hijacking
    • Session fixation
    • Session invalidation
    • Session ID best practices
    • Session handling security considerations in single-page applications
  • Password management
    • Storing account passwords
    • Password in transit
    • Lab – Is just hashing passwords enough?
  • Password storage
    • Dictionary attacks and brute forcing
    • Salting
    • Adaptive hash functions for password storage
    • Lab – Using adaptive hash functions in C#
    • Case study – Veeam missing authentication and cleartext password storage
  • Password policy
  • Password storage – a case study
    • Case study – The Ashley Madison data breach
    • The dictionary attack
    • The ultimate crack
    • Exploitation and the lessons learned
  • Additional password management challenges
    • Password database migration
    • (Mis)handling null passwords
  • Password auditing
    • Using password cracking tools
    • Lab – Password audit with John the Ripper
    • Password recovery issues
    • Password recovery best practices
    • Lab – Password reset weakness
    • Case study – GitLab account takeover
  • Protecting secrets in memory
    • Challenges in protecting memory
    • Case study – Microsoft secret key theft via dump files
    • Storing sensitive data in memory
    • Case study – KeePass password leakage via strings
  • Integrity protection and MAC
    • Integrity protection
    • Message Authentication Code (MAC)
    • Calculating HMAC in C#
    • Lab – Calculating MAC in C#
  • Digital signatures
    • Digital signature
    • Digital signature with RSA
    • ECC basics
    • Digital signature with ECC
    • Digital signature in C#
    • Lab – Digital signature with ECDSA in C#
  • Subresource integrity
    • Importing JavaScript
    • Lab – Importing JavaScript
    • Subresource integrity in Angular
    • Case study – The British Airways data breach
  • Insecure deserialization
    • Serialization and deserialization challenges
    • Integrity – deserializing untrusted streams
    • Integrity – deserialization best practices
    • Look ahead deserialization
  • Property Oriented Programming
    • Property Oriented Programming (POP)
    • Creating a POP payload
    • Lab – Creating a POP payload
  • POP exploitation and best practices
    • Lab – Using the POP payload
    • Summary – POP best practices
    • Case study – Deserialization RCE in Veeam
  • Logging
    • Logging and monitoring principles
    • Insufficient logging
    • Case study – Plaintext passwords at Facebook
    • Logging best practices
  • Log forging
    • Newline injection
    • Web log forging
    • Lab – Log forging
    • Log forging – best practices
  • Monitoring
    • Monitoring best practices
    • Firewalls and Web Application Firewalls (WAF)
    • Intrusion detection and prevention
    • Case study – The Marriott Starwood data breach
  • Principles
    • Error and exception handling principles
    • Information exposure through error reporting
    • Information leakage via error pages
    • Returning a misleading status code
  • Exception handling
    • In the catch block. And now what?
    • Catching NullReferenceException
    • Empty catch block
    • Catching and throwing SystemExceptions
    • Lab – Exception handling mess
  • Control flow and error handling
    • Incorrect block delimitation
    • Dead code
    • Using if-then-else and switch defensively
  • Denial of service
    • Flooding
    • Resource exhaustion
  • Sustained client engagement
    • Infinite loop
    • Denial of service problems in C#
    • Economic Denial of Sustainability (EDoS)
  • Amplification
    • Some amplification examples
  • Algorithmic complexity issues
    • Regular expression denial of service (ReDoS)
    • Lab – ReDoS
    • Dealing with ReDoS
  • Integer handling problems
    • Representing signed numbers
    • Integer visualization
    • Integer overflow
    • Lab – Integer overflow
  • Integer handling problems 2
    • Signed / unsigned confusion
    • Case study – The Stockholm Stock Exchange
    • Lab – Signed / unsigned confusion
    • Integer truncation
  • Integer best practices
    • Upcasting
    • Precondition testing
    • Postcondition testing
    • Using big integer libraries
  • Integer best practices in C#
    • Integer handling in C#
    • Lab – Checked arithmetics
  • Other numeric problems
    • Division by zero
  • Resource leakage
    • Unreleased resource
    • Unreleased resource – Database
    • Unreleased resource – Synchronization
    • Unreleased resource – Various
  • Software security principles
    • Principles of robust programming by Matt Bishop
  • Sources and further readings
    • Software security sources and further reading
    • .NET and C# resources

Pricing

1 year subscription license

599 EUR / person

  • E-learning subscription for sustained readiness
  • Discussion and insight into the hacker’s mindset
  • Hands-on practice, lab exercises using live drills
  • Case studies based on high-profile hacks
Inquiry
Customized course

Tailor a course to your preferences

  • Send us a brief description of your business’s training needs
  • Include your contact information
  • One of our colleagues will be in touch to schedule a free consultation about training requirements
Inquiry

Inquiry

Interested in the trainings but still have some questions? Curious about how you can customize a training for your team? Send us a message and a team member will be in touch within 24 hours.

This field is required

This field is required

Send us your phone number if you prefer to discuss further on a call

This field is required

This field is required

This field is required

This field is required