There are a couple of manner ins which lawbreakers can acquire zero-day malware:
1. They can purchase it on the black market.
2. They can create it themselves.
3. They can take it from a legitimate company or person.
4. They can discover it in the wild.
see this site The most typical manner in which bad guys acquire zero-day malware is by purchasing it on the black market. There are a number of black markets that offer zero-day malware, and the costs can vary depending on the need and the sophistication of the malware.
Lawbreakers can also develop zero-day malware themselves, although this is less common. In order to do this, they would require to have a great understanding of computer system security and exploits.
Another way that bad guys can get zero-day malware is by stealing it from a genuine company or person. This can be done by hacking into a company's network and stealing the malware, or by social engineering a company or person into providing the malware.
Bad guys can discover zero-day malware in the wild. When a security scientist finds a brand-new vulnerability and writes a make use of for it, this generally takes place. The researcher might then sell the make use of to a criminal group, or the exploit may be dripped online.