When these vulnerabilities are identified, companies release software updates to patch the issue and prevent viruses and other malware infections from spreading. Malware also spreads through vulnerabilities in outdated software.

When you download an app from a disreputable source outside Apple’s App Store or Google Play, it can come packaged with malicious software or bloatware. Viruses and other malware can also spread through file sharing and software bundles. That causes the virus infection to spread exponentially - especially if your contacts don’t know the difference between a fake virus warning and real malware detection on their device.Įmail is one of the most popular malware delivery methods, so email security is critical. A virus might email itself out to your contacts, who then unwittingly send it to their contacts, and so on. Once inside your Mac or PC, they make copies of themselves and spread via infected email attachments, poisoned macros, or malicious links.

Computer viruses spread by self-replication.

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