A hacked website by a high profile hacker can be seen easily, because normally they will just replace the index page to let everyone know what they had done. But injected code can be hidden/anonymous, and it’s always too late when you found out because the damage had been done. To detect this earlier, there is a tool where you can use to run a quick scan on your website.
The tool will run a quick scan on your website index page. If no suspicious code found, a result will be display as below:
status: Verified Clean web trust: Not Blacklisted
And a simple report will can be view
If malicious content is found in the index page, the result will display something like:
status: Site infected with malware
If this appear, you may scroll down to the report part to check the suspicious content the tool able to found. There will be a part in the report where suspicious content in the index file printed on the report. And if you are sure the printed part is malicious content, you may proceed to remove it in your index file.
There will be several external tests that recommended to be run at the report part, which worth the time to do.
This Free Website Security Tools and Services site provides a list of website security scanning tool, which allow you to have few more choices while looking for website security.