CS.HCC

Use of hard-coded credentials (password and username)

If software contains hard-coded credentials for authentication, the software is highly vulnerable to attacks because a malicious user has the opportunity to extract this information from the executable file.

The HCC checker detects the use of hard-coded credentials--passwords and usernames--as parameters for authentication functions. The HCC checker also detects cases where software compares user credentials with internal hard-coded values in back-end applications. Hard-coded credentials may not only be coded as credentials used to authenticate a function; they may also be used as a hard-coded check. If a username or a password of an authentication function is compared to a hard-coded string, this is also a vulnerability. By default, this checker considers the functions from popular software libraries, but can also be configured to detect custom authentication functions.

Vulnerability and risk

The use of hard-coded credentials makes it possible for an attacker to extract the credentials from the executable file and bypass the authentication. Hard-coded credentials create a significant risk that may be difficult to detect and to fix.

Mitigation and prevention

For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. For inbound authentication: Rather than hard-code a default username and password, key, or other authentication credentials for first time logins, implement a "first login" mode that requires the user to enter a unique strong password or key.

Vulnerable code example 1

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   namespace HCC
   {
       class Program
       {
           int VerifyAdminUserPassword(String userPassword)
           {
               if (userPassword.Equals("username:pwd@123"))
               {
                   Console.WriteLine("Entering Diagnostic Mode...");
                  return (1);
              }
              Console.WriteLine("Incorrect user or password");
              return (0);
          }
      }
  }

In this example, Klocwork reports a defect at line 7, indicating, "Use of a hardcoded credentials through the call to function 'System.String.Equals'."

Fixed code example 1

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   namespace Data
   {
       public class Database
       {
           public static int VerifyUserPwd(string userPassword)
           {
               //verify user and pwd at database
               return 1;
           }
      }
  }
  
  namespace HCC
  {
      class Program
      {
          int VerifyAdminUser(String userPassword)
          {
             return Data.Database.VerifyUserPwd(userPassword);
          }
      }
  }

In this fixed example, Klocwork no longer reports a defect.

Vulnerable code example 2

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   namespace HCC
   {
       class Program
       {
           public static bool mySqlConnection()
           {
               string cs = "server=localhost;user=root;database=sakila;port=3306;password=your_password";
               using (MySqlConnection conn = new MySqlConnection(cs))
               {
                  //Do operation
              }
              return true;
          }
      }
  }

In this example, Klocwork reports a defect at line 8, indicating, "Use of hardcoded credentials through the call to function 'MySql.Data.MySqlClient.MySqlConnection.#constructor"

Fixed code example 2

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   namespace HCC
   {
       class Program
       {
           private static string getString()
           {
               //Implementation
               throw new NotImplementedException();
           }
          public static bool mySqlConnection( )
          {
              string cs = getString();
              using (MySqlConnection conn = new MySqlConnection(cs))
              {
                  //perform operation
              }
              return true;
          }
      }
  }

In this corrected example, Klocwork no longer reports a defect.

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