Hi @rahulvaishnav,
We are very sorry about the inconvenience this has caused you.
Please make sure you update the File Manager plugin to v6.9 if you are using File Manager Free, or to v7.9 if you are using File Manager Pro. Here is some documentation to assist you with the process: https://filemanagerpro.io/article/how-to-download-latest-version-of-file-manager-pro/
The next step will be to run a service to clean up the malware from your website. We recommend you install Sucuri Malware scanner to assist. This plugin will help you scan and remove Malware from your website.
https://www.ads-software.com/plugins/sucuri-scanner/
Please let me know if you have any further questions.