as to your explanation, yes, Ublock is meant for preventing annoying ads on websites.
No, it's its main use, but it's meant and designed for query filtering. Therefore you can filter whatever, from ads to the annoying, but totally safe, parts of a particular site.
the truth is, downloading a download from the internet is not safe, on here, or even anywhere on the internet. reason being is because firstly, its uploaded by another person, that person can be anyone. also, you are not only putting trust in the uploader but are also willing to download something across the internet which may or not be risky to download.
There's way more reasons why it's never totally safe.
The uploader can be 100% worthy (your brother by example) and yet it would still be safe only up to 99%. This because you've no guaranties that the file you get is the one he uploaded.
The file can have been corrupted by the hosting site, or by someone who compromised the hosting site. And here no one is safe, in the early 2000, the OpenBSD repository have been compromised and was offering corrupted files. So, if the servers from an OS design over the principle that "paranoia is the best security", and that let you do nothing by default, can be compromised, any hosting site can. And the file can also be corrupted during the download. It's less easy but yet still possible.
A solution to this is the signature hash. But even this do not guaranty the security at 100%, unless (to keep my example) it's your brother who gave it to you, and he gave it through another media that the one where you'll get the file. But when it's the hosting site that provide it, you have no guaranties that the hash haven't been generated/changed after the file corruption.
This is why a good virus protection program is paramount to have.
Assumed that you aren't a big target and therefore will never get zero days exploit or code.
And "big target" doesn't necessarily mean that you are someone important. By example, the secretary of some CEO isn't that important, but she's also a perfect entry point to the company network. She's less trained in computer security, and therefore more pron to do some transfer from her home computer to her work one, while having higher privileges than most of the other people in the company.
viruses are getting even smarter these days, some can even cling on and attach to firewalls.
What is far to be something new. My times as security admin start to date and my memory isn't what it used to be, but it was already happening in the early 2000.
Despite this, taking security measures to high priority is needed. Hell, encryption of drives, maximum network protection, virus protection program, encrpytion of data files or important files, are just a few methods to stay protected.
This is a really bad advice.
Of course, I'll not say that people don't need to be protected, but too many protections, especially when handled by someone that haven't been trained to use them, will lower the level of security, not increase it.
There's a reason why nowadays high level security suits are operated on separated computers, one by element of the suit. It's because they tend to interact too intensively and it tend to create holes in their points of collision.
For a personal use, an anti-virus coupled to a sandbox, doubled with good practices, are enough to cover 99% of the risks. For a more advanced use, an ip filter coupled with a proxy, both on separated computers in the LAN, cover the rest.
But anyway, whatever you are doing, you'll never goes higher than 99%.
