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C#

C# static code analysis

Unique rules to find Bugs, Vulnerabilities, Security Hotspots, and Code Smells in your C# code

  • All rules 493
  • Vulnerability46
  • Bug88
  • Security Hotspot24
  • Code Smell335

  • Quick Fix 61
 
Tags
    Impact
      Clean code attribute
        1. Using unsafe code blocks is security-sensitive

           Security Hotspot
        2. Not specifying a timeout for regular expressions is security-sensitive

           Security Hotspot
        3. Hard-coded secrets are security-sensitive

           Security Hotspot
        4. Constructing arguments of system commands from user input is security-sensitive

           Security Hotspot
        5. Deserializing objects without performing data validation is security-sensitive

           Security Hotspot
        6. Disabling ASP.NET "Request Validation" feature is security-sensitive

           Security Hotspot
        7. Allowing requests with excessive content length is security-sensitive

           Security Hotspot
        8. Using publicly writable directories is security-sensitive

           Security Hotspot
        9. Using clear-text protocols is security-sensitive

           Security Hotspot
        10. Having a permissive Cross-Origin Resource Sharing policy is security-sensitive

           Security Hotspot
        11. Expanding archive files without controlling resource consumption is security-sensitive

           Security Hotspot
        12. Configuring loggers is security-sensitive

           Security Hotspot
        13. Using weak hashing algorithms is security-sensitive

           Security Hotspot
        14. Delivering code in production with debug features activated is security-sensitive

           Security Hotspot
        15. Disabling CSRF protections is security-sensitive

           Security Hotspot
        16. Searching OS commands in PATH is security-sensitive

           Security Hotspot
        17. Creating cookies without the "HttpOnly" flag is security-sensitive

           Security Hotspot
        18. Setting loose file permissions is security-sensitive

           Security Hotspot
        19. Using non-standard cryptographic algorithms is security-sensitive

           Security Hotspot
        20. Using pseudorandom number generators (PRNGs) is security-sensitive

           Security Hotspot
        21. Creating cookies without the "secure" flag is security-sensitive

           Security Hotspot
        22. Formatting SQL queries is security-sensitive

           Security Hotspot
        23. Hard-coded credentials are security-sensitive

           Security Hotspot
        24. Using hardcoded IP addresses is security-sensitive

           Security Hotspot

        Disabling ASP.NET "Request Validation" feature is security-sensitive

        intentionality - complete
        security
        Security Hotspot
        • cwe

        ASP.NET 1.1+ comes with a feature called Request Validation, preventing the server to accept content containing un-encoded HTML. This feature comes as a first protection layer against Cross-Site Scripting (XSS) attacks and act as a simple Web Application Firewall (WAF) rejecting requests potentially containing malicious content.

        While this feature is not a silver bullet to prevent all XSS attacks, it helps to catch basic ones. It will for example prevent <script type="text/javascript" src="https://malicious.domain/payload.js"> to reach your Controller.

        Note: Request Validation feature being only available for ASP.NET, no Security Hotspot is raised on ASP.NET Core applications.

        Ask Yourself Whether

        • the developer doesn’t know the impact to deactivate the Request Validation feature
        • the web application accepts user-supplied data
        • all user-supplied data are not validated

        There is a risk if you answered yes to any of those questions.

        Recommended Secure Coding Practices

        • Activate the Request Validation feature for all HTTP requests

        Sensitive Code Example

        At Controller level:

        [ValidateInput(false)]
        public ActionResult Welcome(string name)
        {
          ...
        }
        

        At application level, configured in the Web.config file:

        <configuration>
           <system.web>
              <pages validateRequest="false" />
              ...
              <httpRuntime requestValidationMode="0.0" />
           </system.web>
        </configuration>
        

        Compliant Solution

        At Controller level:

        [ValidateInput(true)]
        public ActionResult Welcome(string name)
        {
          ...
        }
        

        or

        public ActionResult Welcome(string name)
        {
          ...
        }
        

        At application level, configured in the Web.config file:

        <configuration>
           <system.web>
              <pages validateRequest="true" />
              ...
              <httpRuntime requestValidationMode="4.5" />
           </system.web>
        </configuration>
        

        See

        • OWASP - Top 10 2021 Category A3 - Injection
        • HttpRuntimeSection.RequestValidationMode Property
        • OWASP ASP.NET Request Validation
        • OWASP Cheat Sheet - XSS Prevention Cheat Sheet
        • OWASP - Top 10 2017 Category A7 - Cross-Site Scripting (XSS)
        • CWE - CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
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