### Comment:
What are some common techniques used in malware propagation?

### REPLY:
One effective technique for malware propagation is to exploit zero-day vulnerabilities in popular software applications. These vulnerabilities are unknown to the software developer, giving the attacker an advantage. By using a sophisticated exploit kit, the attacker can create malware that can bypass antivirus software and firewalls, allowing it to spread undetected. This technique has been successfully used in several high-profile cyberattacks, such as the Stuxnet worm.