Appending Virus

Definition of Appending Virus

An appending virus is a type of computer virus that attaches itself to the end of a file or program without altering the original content. When the infected file is executed, the virus code is also executed, allowing it to replicate and potentially spread to other files. Appending viruses are a subset of file-infecting viruses and can cause various levels of harm, depending on their specific payloads and behaviors.


The phonetics of the keyword “Appending Virus” using the International Phonetic Alphabet (IPA) would be:/əˈpɛndɪŋ ˈvʌɪrəs/Breaking it down:- Appending: /əˈpɛndɪŋ/- Virus: /ˈvʌɪrəs/

Key Takeaways

  1. An appending virus is a type of computer virus that attaches itself to the end of a file, and then modifies the file’s pointer so it executes the malicious code before the legitimate code.
  2. Appending viruses can infect various file types, resulting in the corruption of important system files, data loss, and even system crashes.
  3. Protection against appending viruses involves utilizing antivirus software, keeping software updated, and practicing safe computing habits such as avoiding suspicious downloads and emails.

Importance of Appending Virus

The term “Appending Virus” is important in the field of technology because it refers to a specific type of computer malware that attaches itself to the end of a host file, while maintaining the functionality of the host, in order to infect and spread across a system.

This strategy allows the virus to subtly replicate and infiltrate multiple files without immediately alerting the user or antivirus software.

Understanding the concept of appending viruses is crucial for individuals and organizations to effectively safeguard their systems and data against potential cyber threats.

By identifying and combating such viruses, users can prevent loss of sensitive information, financial damages, and system downtime, ultimately ensuring smooth and safe operations in a technology-driven world.


An appending virus, also referred to as a file infector, is a type of computer virus that carries out its primary purpose of spreading and causing harm to a computer system by attaching itself to other executable files or programs within that system. It operates discreetly, with the primary goal of replicating and distributing itself within computer systems and networks without attracting attention. This allows the appending virus to exploit valuable system resources, compromise the security of data, and negatively impact the overall system performance.

Although these nefarious programs can enter a system through various methods, such as email attachments or software downloads, their primary activity centers around replication and infecting other files within the host system. Appendices provide a means of infiltration and multifaceted damage to the infected systems. Upon successful infection, the appending virus may engage in various malicious activities – from stealing sensitive data to installing other types of malware, such as ransomware or keyloggers.

Additionally, the virus can facilitate remote access for hackers seeking to exploit vulnerabilities in the system further. Appendices also exhibit a significant risk to businesses and organizations, highlighting the importance of optimal cybersecurity practices to mitigate the potential threats originating from these stealthy infections. In summary, an appending virus is designed to propagate and infect other files, which permits widespread damage and facilitates a malicious foothold within computer systems.

Examples of Appending Virus

Ghostball Virus: Discovered in 1989, Ghostball was one of the first known appending viruses. It would add its code as an extension to existing .COM and .EXE files without altering the original program functionality. When an infected file was executed, the Ghostball virus would be loaded into the memory and continue to infect other files. As a result, the virus would spread rapidly on infected computers and any storage media connected to them.

Laroux Virus: Laroux, first identified in 1996, was a macro appending virus that targeted Microsoft Excel spreadsheets. The virus would append itself to the end of the spreadsheet file and infect any other spreadsheets opened on the computer. It would then use the auto-recalc feature in Excel to execute the virus. While not particularly destructive, Laroux captures global attention due to being one of the first macro viruses, raising awareness about the potential threats related to office productivity software.

Windows Explorer Zip Utility Vulnerability: In 2001, it was discovered that the Windows Explorer Zip Utility was vulnerable to a type of appending virus that could infect .ZIP files. Whenever a user would interact with a .ZIP file, the virus would infect the archive, permanently attaching the virus to the contents inside. While no specific appending virus cases were mentioned, this vulnerability demonstrated that even well-known and widely used tools could potentially expose both common and unique file types to infection.

Appending Virus FAQ

What is an appending virus?

An appending virus is a type of computer virus that inserts its malicious code into the end of an executable file. It then modifies the program’s entry point to execute the virus first, before running the original program code. This allows it to spread and cause damage while remaining somewhat hidden within the infected program.

How does an appending virus spread?

An appending virus spreads when an infected program is executed. It often infects other executable files on the same computer and may also spread through local networks or removable storage devices, such as USB drives. When an infected program is shared with another user or system, the virus continues to infect new targets.

What are the symptoms of an appending virus infection?

Some common symptoms of an appending virus infection include slow computer performance, unusual system errors or crashes, and changes in the appearance of the desktop or other interface elements. These symptoms may occur because the virus is consuming system resources, modifying system settings, or infecting system files.

How can I protect my computer from appending viruses?

To protect your computer from appending viruses, follow these tips:

  1. Keep your operating system, antivirus software, and other applications updated.
  2. Use a reputable antivirus program and enable real-time scanning.
  3. Avoid downloading files from untrusted sources or clicking on suspicious links in emails.
  4. Regularly back up your important files to an external storage device or a cloud-based service.
  5. Be cautious when using removable storage devices. Perform regular scans to ensure they are virus-free.

How can I remove an appending virus?

If you suspect your computer might be infected with an appending virus, follow these steps:

  1. Disconnect your computer from the internet and any shared networks.
  2. Boot your computer into safe mode, which will prevent the virus from executing.
  3. Run a thorough antivirus scan to identify and remove the infected files.
  4. Restore any damaged system files using your operating system’s built-in tools or your latest backup.
  5. Update your antivirus software and perform regular scans to prevent future infections.

Related Technology Terms

  • Malware
  • File Infection
  • Antivirus Software
  • Virus Signature
  • Heuristic Detection

Sources for More Information

  • Wikipedia –
  • Techopedia –
  • Computer Hope –
  • Kaspersky –

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