How to Check if an IP Address is a Known Security Threat in C#

It’s a good idea to implement basic security policies against IP addresses which are known for malicious activities. Leveraging the free-to-use IP Threat Detection API provided in this article makes it easy to check against a long list of bad IP’s, botnets, compromised servers, and much more.

You can easily take advantage of this API using the ready-to-run C# code examples provided below.

First, you’ll need to run the below command in the Package Manager console. This installs the client SDK via NuGet:

Install-Package Cloudmersive.APIClient.NET.Security -Version 3.0.1

After that, you can copy the below code to structure your API call. You’ll need a free-tier API key (good for 800 API calls per month) to authenticate your request:

using System;
using System.Diagnostics;
using Cloudmersive.APIClient.NET.Security.Api;
using Cloudmersive.APIClient.NET.Security.Client;
using Cloudmersive.APIClient.NET.Security.Model;

namespace Example
{
    public class NetworkThreatDetectionIsThreatExample
    {
        public void main()
        {
            // Configure API key authorization: Apikey
            Configuration.Default.AddApiKey("Apikey", "YOUR_API_KEY");

            var apiInstance = new NetworkThreatDetectionApi();
            var value = value_example;  // string | IP address to check, e.g. \"55.55.55.55\".  The input is a string so be sure to enclose it in double-quotes.

            try
            {
                // Check if IP address is a known threat
                IPThreatDetectionResponse result = apiInstance.NetworkThreatDetectionIsThreat(value);
                Debug.WriteLine(result);
            }
            catch (Exception e)
            {
                Debug.Print("Exception when calling NetworkThreatDetectionApi.NetworkThreatDetectionIsThreat: " + e.Message );
            }
        }
    }
}

Now you can easily defend your system against malicious IPs and the various forms they take.