What is Malware?
Malware is any type of software created to harm or exploit another piece of software or hardware. Short for "malicious software", malware is a collective term used to describe viruses, ransomware, spyware, Trojans, and any other type of code or software built with malicious intent.
It's this malicious intent that characterizes the malware definition - the meaning of malware is the damage it can inflict on a computer, computer system, server, or network. It's the how and the why that separate one type of malware from the next.
There are different types of malware, each with its threat level.
Malware has the following objectives:
- Send spam from the infected computer to other systems.
- Provide an attacker with remote access to an infected computer.
- Access the infected user's local network.
- Steal sensitive information.
Types of malware
Virus
Viruses are a subgroup of malware. A virus is malicious software attached to a document or file that supports macros to execute its code and spread from host to host. Once downloaded, the virus will lay dormant until the file is opened and in use. Viruses are designed to disrupt a system's ability to operate. As a result, viruses can cause significant operational issues and data loss.
Macro viruses
Macro viruses are a type of virus that exploit macros in Microsoft Office apps like Word and Excel to infect your device.
Router viruses
Your Wi-Fi router can also become infected with malware. Router malware usually redirects you to malicious pharming websites that can capture your personal data, and removing router viruses can be tricky.
Ransomware
Ransomware is malicious software that gains access to sensitive information within a system, encrypts that information so that the user cannot access it, and then demands a financial payout for the data to be released. Ransomware is commonly part of a phishing scam. By clicking a disguised link, the user downloads the ransomware. The attacker proceeds to encrypt specific information that can only be opened by a mathematical key they know. When the attacker receives payment, the data is unlocked.
Spyware
Spyware is malicious software that runs secretly on a computer and reports back to a remote user. Rather than simply disrupting a device's operations, spyware targets sensitive information and can grant remote access to predators. Spyware is often used to steal financial or personal information. A specific type of spyware is a keylogger, which records your keystrokes to reveal passwords and personal information.
Trojan virus
Trojan viruses are disguised as helpful software programs. But once the user downloads it, the Trojan virus can gain access to sensitive data and then modify, block, or delete the data. This can be extremely harmful to the performance of the device. Unlike normal viruses and worms, Trojan viruses are not designed to self-replicate.
Worms
Worms are a malicious software that rapidly replicates and spreads to any device within the network. Unlike viruses, worms do not need host programs to disseminate. A worm infects a device via a downloaded file or a network connection before it multiplies and disperses at an exponential rate. Like viruses, worms can severely disrupt the operations of a device and cause data loss.
Adware
Adware is malicious software used to collect data on your computer usage and provide appropriate advertisements to you. While adware is not always dangerous, in some cases adware can cause issues for your system. Adware can redirect your browser to unsafe sites, and it can even contain Trojan horses and spyware. Additionally, significant levels of adware can slow down your system noticeably. Because not all adware is malicious, it is important to have protection that constantly and intelligently scans these programs.
Fileless malware
Fileless malware is a type of memory-resident malware. As the term suggests, it is malware that operates from a victim's computer's memory, not from files on the hard drive. Because there are no files to scan, it is harder to detect than traditional malware. It also makes forensics more difficult because the malware disappears when the victim computer is rebooted. In late 2017, the Cisco Talos threat intelligence team posted an example of fileless malware that they called DNSMessenger.
Scams
Trick users with fake travel promotions or winning lottery tickets, asking for money to provide access to the 'prize'.
Keyloggers
Just like any other malware, keylogging software spreads mostly via the Internet, often as part of Trojans. Trojans are programs disguised as useful tools, which in reality contain malware that gets installed on your computer without your knowledge. Once installed, keyloggers run in the background, recording all your keystrokes.
The stolen information is usually encrypted and sent to a public message board, where hackers can download it without being tracked down.
Exploits
Take advantage of security holes or vulnerabilities in communications protocols to enter computers.
Scareware
Scareware uses social engineering tricks to frighten you into installing it. A fake pop-up warns you that your computer is infected with a virus, and the solution will be to download a scam "security" program.
Bots
Programs which, once installed on a computer, allow the attacker to take control of it remotely.
How to protect yourself from malware
Malware will inevitably penetrate your network. You must have defenses that provide significant visibility and breach detection. In order to remove malware, you must be able to identify malicious actors quickly. This requires constant network scanning. Once the threat is identified, you must remove the malware from your network. Today's antivirus products are not enough to protect against advanced cyber threats.
- Don't trust strangers online. Strange emails, abrupt alerts, fake profiles, and other scams are the most common methods of delivering malware. If you don't know exactly what something is, don't click on it.
- Double-check your downloads. From pirating sites to official storefronts, malware is often lurking just around the corner. Before downloading, always double-check that the provider is trustworthy.
- Get an ad blocker. Malvertising - where hackers inject malicious code into otherwise legitimate advertising networks - is on the rise. Counter it by blocking ads with a reliable ad blocker. Some infected ads can download malware as soon as they load on your screen, without needing you to even click on them.
- Be careful where you browse. Malware can be found anywhere, but it's most commonly found on websites with poor backend security. If you're visiting a large, reputable site, your risk of encountering malware is minimal.
- Always update your software. Outdated software may have security vulnerabilities, which developers routinely patch with software updates. Always install updates for your operating system (OS) and other software as soon as they become available.
- Protect your devices with an antivirus app. Even if you follow all of the advice above, your device might still get infected with malware.
