How can I make a third-party site display different information on a specific computer?

Question

Browsers

Hi all. I wondered if it is possible to change the information on the site on a specific computer? So that when the page is refreshed, the information remains saved, and not reset. Naturally on a specific computer. For example, to withdraw a completely different amount on cards to Sberbank online than it actually is (I repeat, when you enter from a specific computer, there will be real info from another).

Answer 1

If you need changes on the page:
If you have access to this computer, you can install a browser extension that will replace the content of the page. The same Greasemonkey / Tampermonkey, these are user scripts in the browser that are triggered by a condition (for example, pages / domain) and do whatever you want from them.
If you need significant changes (actually a different website):
then, as already described here, you need to change the dns entry in your dns server or simply fix the hosts file (in windows it's C:\Windows\System32\drivers\etc\ ) by specifying to your ip address of this server, where you launch your fake.
You can also raise your proxy server, register it in the browser settings and make a substitution in it.
In this case, https will not work, more precisely, a warning about an untrusted certificate will pop up, but if you have access to a computer, this can be partially fixed by adding your certificate to the browser (for banking web servers, a more complex certificate is used when company information is displayed directly in green to the left of the link, this cannot be faked), simple certificates are simply marked with a green icon without a company name.

Answer 2

set up your web server, and on the attacked computer in the hosts file, redirect the desired domain to your server. Do whatever you want on your server - at least forge the page, at least change the values. Everything is done by hand.
The second way is to enter a proxy for the victim, raise your proxy, and by intercepting requests, change values ​​on the fly.
But all antiviruses and modern browsers will not let you access the Sberbank domain via the https protocol if it leads not to the Sberbank address, but to your replacement host.
In the case of a proxy, you won’t even see the insides of the transmitted content with the https protocol, which is why it was invented.

Answer 3

Can.
BUT difficult.
To crash into https, on which all client-banks work, bumping is needed. That is, you need to force this computer to go through a proxy and, moreover, force the user to register the certificate of the CA that issued the certificate to the proxy (which is used for bumping) - to the trusted ones. And all the same, it may not work - if the bank, for example, uses pinning.
If all this is there, then you can change the content of the pages directly directly on the proxy.