How to Block Malicious Uploads in Javascript

File uploads are one of the most dangerous threats this year, with the victim count constantly rising each day. It is essential to have a means of protection against this type of attack if your website is to avoid a gruesome fate. In today’s article, we will be showcasing an easy to set up API that provides advanced scanning as well as zero-day threat capabilities through customizable options.

Let’s add our client library with the following script tag:

<script src="https://cdn.cloudmersive.com/jsclient/cloudmersive-virus-client.js"></script>

Now scanFileAdvanced can be called. By default, all of the security options are enabled, protecting you from scripts, executables, invalid files, and password protected files. Not to mention triple layered virus scanning.

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 there you have it! It’s as easy as that.

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