Modern malware (malicious code) can be hidden in many types of files and infect computers, phones or other devices when these files are activated by devices or programs/apps on these devices.
Meduza (see [1]) can steal info from 19 password manager apps, 76 crypto wallets and 95 web browsers, as well as apps Discord and Steam. It also able to modify itself and hide from malware detection tools.
Such malware can be used to execute very sophisticated cyber attacks (see [2]). A free tool (see [3-4]) allows anyone to test any file or URL on malware infections.
References:
[1] Meduza malware
[2] How sophisticated modern hackers are
https://www.youtube.com/watch?v=f-TL7tqITcg
