How to Block Threats in File Uploads in Node.JS

One of the most dangerous cyber attack vectors this year is the file upload form. This can be taken advantage of in any number of different ways by the aspiring hacker, including infected files, masked executables, and hidden scripts. Without adequate defense from such attacks, your site will be utterly vulnerable, at the mercy of these miscreants. Today, I will be demonstrating a very simple means of eliminating these threats before they can cause any damage to your system. By using a highly advanced virus scanning API with zero day threat capability, you will be clad in virtual armor in a matter of a few minutes.

The first step is to install the client library:

npm install cloudmersive-virus-api-client --save

Now we can call scanFileAdvanced using our file. By default, this will filter out invalid files, executables, scripts, and password protected files, as well as perform a 3-layer ultra-sensitive virus scan.

var CloudmersiveVirusApiClient = require('cloudmersive-virus-api-client');var defaultClient = CloudmersiveVirusApiClient.ApiClient.instance;// Configure API key authorization: Apikeyvar Apikey = defaultClient.authentications['Apikey'];Apikey.apiKey = 'YOUR API KEY';// Uncomment the following line to set a prefix for the API key, e.g. "Token" (defaults to null)//Apikey.apiKeyPrefix = 'Token';var apiInstance = new CloudmersiveVirusApiClient.ScanApi();var inputFile = "/path/to/file"; // File | Input file to perform the operation on.var opts = {'allowExecutables': true, // Boolean | Set to false to block executable files (program code) from being allowed in the input file.  Default is false (recommended).'allowInvalidFiles': true, // Boolean | Set to false to block invalid files, such as a PDF file that is not really a valid PDF file, or a Word Document that is not a valid Word Document.  Default is false (recommended).'allowScripts': true, // Boolean | Set to false to block script files, such as a PHP files, Pythong scripts, and other malicious content or security threats that can be embedded in the file.  Set to true to allow these file types.  Default is false (recommended).'allowPasswordProtectedFiles': true, // Boolean | Set to false to block password protected and encrypted files, such as encrypted zip and rar files, and other files that seek to circumvent scanning through passwords.  Set to true to allow these file types.  Default is false (recommended).'restrictFileTypes': "restrictFileTypes_example" // String | Specify a restricted set of file formats to allow as clean as a comma-separated list of file formats, such as .pdf,.docx,.png would allow only PDF, PNG and Word document files.  All files must pass content verification against this list of file formats, if they do not, then the result will be returned as CleanResult=false.  Set restrictFileTypes parameter to null or empty string to disable; default is disabled.};var callback = function(error, data, response) {if (error) {console.error(error);} else {console.log('API called successfully. Returned data: ' + data);}};apiInstance.scanFileAdvanced(inputFile, opts, callback);

And that’s all there is to it! You are secure.

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