What Is a Computer Virus?

Threat Type: Computer Virus

Category: Malware-Based Threat

Cyber Threat Indicators

A computer virus is a type of malicious software, that infects a computer, it's designed to replicate itself and spread to other programs, files, or computers.

Core Characteristics

Host Dependency: A virus cannot run or replicate on its own; it must attach itself to a legitimate program, file, or document (the "host") to execute its code.

Self-Replication (Replication Mechanism): Once executed, the virus has the ability to make copies of itself and insert those copies into other files on the same computer or network. This is its primary method of spreading infection.

Activation Mechanism: The virus often remains dormant until a specific event or condition—the trigger—is met. This trigger could be opening the infected file, a specific date/time, or a certain number of reboots.

Payload Execution (Objective): This is the malicious action the virus is programmed to perform once activated. The payload can range from minor annoyances (like pop-up messages) to serious damage, such as corrupting data, slowing performance, or compromising system security.

Common Examples

Trojan Horse malware disguises itself as legitimate, useful software to trick the user into installing it. It does not replicate itself. Often found in fake software downloads, pirated media, or attached to phishing emails.

Worm self-replicating malware that spreads independently across computer networks without needing a host program or user action to execute. Exploits security vulnerabilities in operating systems or network software to spread rapidly.

Ransomware encrypts a victim's files, effectively holding them hostage until a ransom is paid (usually in cryptocurrency). Delivered via malicious email attachments, infected websites, or through other malware like Trojans or Worms.

Spyware software designed to secretly observe and record a user's activities without their consent. Often bundled with legitimate-looking software or installed via malicious links; includes keyloggers (recording keystrokes).

Macro Virus written in a macro language (like those used in Microsoft Office) that infects document files (e.g., Word, Excel). Spreads when a user opens an infected document and enables its macros.

Common Tactics

Infected Email Attachments: The most common method, often disguised as invoices, shipping notifications, or other urgent messages.

Malicious Downloads: Hiding the virus or other malware inside seemingly harmless files downloaded from suspicious websites.

Network Vulnerabilities: Exploiting known flaws in operating systems or network protocols to automatically jump from one computer to another (a common worm tactic).

---

VIIEGO the human security agency for human security research and consulting in identity manipulation and fraud prevention to decode human behavior and secure your identity.

www.viiego.com | Protect What's Yours.