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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

        Using hardcoded IP addresses is security-sensitive

        responsibility - trustworthy
        security
        Security Hotspot

          Hardcoding IP addresses is security-sensitive. It has led in the past to the following vulnerabilities:

          • CVE-2006-5901
          • CVE-2005-3725

          Today’s services have an ever-changing architecture due to their scaling and redundancy needs. It is a mistake to think that a service will always have the same IP address. When it does change, the hardcoded IP will have to be modified too. This will have an impact on the product development, delivery, and deployment:

          • The developers will have to do a rapid fix every time this happens, instead of having an operation team change a configuration file.
          • It misleads to use the same address in every environment (dev, sys, qa, prod).

          Last but not least it has an effect on application security. Attackers might be able to decompile the code and thereby discover a potentially sensitive address. They can perform a Denial of Service attack on the service, try to get access to the system, or try to spoof the IP address to bypass security checks. Such attacks can always be possible, but in the case of a hardcoded IP address solving the issue will take more time, which will increase an attack’s impact.

          Ask Yourself Whether

          The disclosed IP address is sensitive, e.g.:

          • Can give information to an attacker about the network topology.
          • It’s a personal (assigned to an identifiable person) IP address.

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

          Recommended Secure Coding Practices

          Don’t hard-code the IP address in the source code, instead make it configurable with environment variables, configuration files, or a similar approach. Alternatively, if confidentially is not required a domain name can be used since it allows to change the destination quickly without having to rebuild the software.

          Sensitive Code Example

          var ip = "192.168.12.42";
          var address = IPAddress.Parse(ip);
          

          Compliant Solution

          var ip = ConfigurationManager.AppSettings["myapplication.ip"];
          var address = IPAddress.Parse(ip);
          

          Exceptions

          No issue is reported for the following cases because they are not considered sensitive:

          • Loopback addresses 127.0.0.0/8 in CIDR notation (from 127.0.0.0 to 127.255.255.255)
          • Broadcast address 255.255.255.255
          • Non-routable address 0.0.0.0
          • Strings of the form 2.5.<number>.<number> as they often match Object Identifiers (OID)
          • Addresses in the ranges 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, reserved for documentation purposes by RFC 5737
          • Addresses in the range 2001:db8::/32, reserved for documentation purposes by RFC 3849

          See

          • OWASP - Top 10 2021 Category A1 - Broken Access Control
          • OWASP - Top 10 2017 Category A3 - Sensitive Data Exposure
            Available In:
          • SonarQube IdeCatch issues on the fly,
            in your IDE
          • SonarQube CloudDetect issues in your GitHub, Azure DevOps Services, Bitbucket Cloud, GitLab repositories
          • SonarQube Community BuildAnalyze code in your
            on-premise CI
            Available Since
            9.1
          • SonarQube ServerAnalyze code in your
            on-premise CI
            Developer Edition
            Available Since
            9.1

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