I'm pretty sure that crack tools are detected as malware or viruses because, by definition, they are. Its specific purpose is to modify programs and files so that they do not work as designed. They delete the verification files, modify the state of the registry, and do everything they can to prevent their target from working as intended. The goal of a crack is to alter an exe file, which is a red flag for the activity of the virus, even if it isn't.
We can see that the decrypted software contains malware and also the social engineering skills used by the hacker by which the hacker can hack the person who downloads the decrypted software. Always be careful when downloading anything, because of our little mistake we can be hacked. Do not think that the antivirus can protect you, since the antivirus works on the signature pattern that is present in your database and the malware can become FUD (totally undetectable), as there are many techniques to make FUD. Use genuine software provided by the company, as your security is your priority.
Cracks that are also Trojans are particularly dangerous because the hackers who created the malware will not only want it to enter your device without being seen. What I'm trying to say is that just because a crack seems to work well, you shouldn't sit back and relax. Often, the person who installed that software and manages it wants to know that decrypted software has been installed on their machine. However, sometimes people who make cracks available for download (hosters) infect them with an additional Trojan component or spyware, etc.
Applications such as key generation applications seem to be more likely to get infected (which makes sense, since they are smaller and there are no need to decipher a legitimate program first). I know that part of the crack is a fake file to lock your computer or steal private information, but most of them can make the software run in full version. For example, if you're a fan of Xbox Live, testing your chances with cracked games could be a terrible idea. It is not uncommon for known harmless crack signatures to be permanently blacklisted by antivirus software, even if those cracks do not infect your devices and do not collect personal information.
The older the version of software you are using, the greater the risk of malware exploiting vulnerabilities in decrypted software. The scrolling is identified and the code is manipulated to jump, regardless of which serial key is entered, which decrypts the game. Technically, all you need to decrypt a software is a text editor that can edit hexadecimal values in a binary (Hex editing software is suitable for this). Crack is adware software that delivers advertising content to the end user and can be considered invasive of privacy.
There is no such thing as “safe to use” decrypted software, unless you know the SOURCE and trust it, there is no way of knowing what kind of viruses, root kits, Trojans, etc. the one who decrypted the software may have added, AND OFTEN THE SOFTWARE IS NOTHING MORE THAN MALWARE THAT PRETENDS TO BE A CRACK. Even though crack allows you, the user, to use the program for free (that is, you are achieving your goal with the program and making it work the way you want it), AV doesn't care about that. No one has the time or inclination to reverse engineer every distributed copy of every crack on the market, which is part of the reason they are told that there is %3D %3D piracy malware in the first place.