To remove the malware, does it suffice to remove the infected file site/media/system/js/caption.js? Or should I, and how to, further investigate the all the other files?
Thank you in advance for your help.
First of all, many thanks to @begueradj, @Aurora, @André Daniel and @SilverlightFox for their comments and answers. And please forgive me for not replying earlier, I have been involved in another urgent mission and have just finished.
I was so panic that I deleted the infected file, i.e., .../media/system/js/caption.js, and took the site offline. Now what I am planning to do are:
- On localhost: upgrade Joomla! as well as all the installed extensions to the latest versions.
- Move the website to a new hosting.