How does malware commonly infiltrate a computer system?

Malware commonly infiltrates a computer system primarily through infected email attachments or compromised downloads. This method is particularly effective because attackers often use social engineering tactics to trick users into opening malicious files or downloading harmful software. By disguising malware as a legitimate file or program, cybercriminals exploit the trust of users. Email attachments, especially from unknown or seemingly trustworthy sources, can contain viruses or other types of malware that, once activated, can compromise the system. Similarly, downloading software from unreliable or unverified sources can lead to the installation of malware on a device.

While phishing links are a common method for distributing malware, they are not the only way. Other vectors, like compromised downloads, represent a significant portion of malware distribution. Scanning external devices for vulnerabilities often pertains to exploiting known weaknesses rather than a direct means of infiltration, and breaching firewalls typically involves bypassing security measures rather than the initial entry of malware. Therefore, the option highlighting infected email attachments or compromised downloads accurately encompasses a key avenue through which malware is frequently spread.