Short for “malicious software,” malware refers to any intrusive program or code designed by cyber criminals to steal data and destroy or damage computer systems. It is an umbrella term that includes viruses, Trojan viruses, spyware, adware, worms, and ransomware.
All malware is coded to harm computers, mobile devices, networks, and computer systems by invading and taking partial control over their operations. Think of it as the human flu — it messes with the normal functions of your body in a snap.
What is a possible sign of malware? What are its different forms, and how can you prevent it from infecting your devices? In this article, we asked our cybersecurity experts to answer these questions.
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Possible Signs of Malware
Nowadays, online security is a major concern for both small and large corporations, as well as individuals. Malware is becoming more and more common, and most of us are likely aware of the damage it can cause.
Despite the many efforts of professional IT to combat malware, it’s still prevalent and is becoming more sophisticated. Check out the hints and possible signs of malware below:
- Impaired, Slow Performance
- Unexpected and Flooding Pop-Up Ads
- Unexplained Disk Space Loss
- Renamed Files
- Poor Internet Connection
- Sudden Increase in the System’s Internet Activity
- Unresponsive Browser
- Obscure Email Activity
- Random Messages, Music, or Sounds
- Getting Locked Out of Your Accounts
- Unusual Error Messages
- Browser Homepage Changes
- Disabled System Tools and Antivirus Software
- Losing Access to Your Files or Computer
Impaired, Slow Performance
One of the most obvious signs of malware is a noticeably slower device that frequently crashes or freezes. The bootup process may also take up to five to ten minutes, depending on the severity of the problem. When the viruses are active, they consume a substantial amount of memory, which only leaves limited resources for other programs.
Unexpected and Flooding Pop-Up Ads
Adware is malicious software that displays ads on your device, usually as banners or pop-ups, often without your consent. In some cases, it comes bundled with other software that you downloaded intentionally. Adware can track your browsing habits and may not be harmful, but some of them may open the door to more malicious activities.
Unexplained Disk Space Loss
When your device is attacked by malware, you may lose free space on your hard drive without any apparent cause. This happens because many viruses create several copies of themselves whenever you access the disk. The copies are created by the virus code attached to an already running program on your device.
Renamed Files
Renaming system files will prevent the system from working properly and cause damage to the operating system. In some cases, you can remove all traces of the virus and repair your damaged files, but in most cases, you will need to reinstall the operating system and reformat your drive to completely clean your device.
Poor Internet Connection
Malware can deteriorate your connection quality in several ways. It can infect your router or consume your device’s memory by working in the background, leaving limited resources for anything else. The virus may also take up all your available bandwidth if it’s constantly uploading and downloading files in the background. Lastly, viruses may also interfere with your Wi-Fi signal, by emitting a signal of their own.
Sudden Increase in the System’s Internet Activity
As mentioned above, malware can work online in the background, constantly downloading and uploading data, which negatively impacts your system's internet activity.
Unresponsive Browser
Suddenly closing or freezing browsers may also point to malware activity. Your computer might be infected with malware or adware that is preprogrammed to exit your browser when you search for certain keywords related to security tools.
Obscure Email Activity
Malware can hijack devices to send out spam, manipulate email headers overload email servers, or gather sensitive information, which can lead to phishing attacks, mail bombing, spoofing, and data theft.
Random Messages, Music, or Sounds
Potentially Unwanted Programs or PUPs often play annoying sounds and music on an affected device. This type of malware can activate frequently because of specific background activities, such as running advertisements.
Getting Locked Out of Your Accounts
Malware can infiltrate your device and steal sensitive information stored in your system and browser. Cybercriminals may then extort this data, accessing your accounts and changing your credentials to lock you out.
Unusual Error Messages
Malware may trigger rare error messages as it damages your computer’s operating system. In other cases, these error messages may be caused by adware, trying to talk you into downloading an actual virus, or participating in a phishing scheme.
Browser Homepage Changes
Browser hijacker programs can modify your browser settings and redirect you to sites you didn’t intend to visit. These aim to generate fraudulent advertising revenue. For example, the browser redirects you to the cybercriminal’s search page, and then to links the hijacker wants you to see. When you click on any of these links, the hijacker gets paid. In less obtrusive cases, cybercriminals may simply just sell the information about your browsing habits to third parties.
Disabled System Tools and Antivirus Software
Malware can disable antivirus software and system tools to avoid detection and keep control over the infected system. By disabling these scanners and tools, viruses can operate freely in your system, preventing quarantine and allowing further spread.
Losing Access to Your Files or Computer
In some cases, ransomware can encrypt files on your device and demand payment for the decryption key. In other cases, a virus can delete or corrupt files, making them inaccessible. Some viruses can also lock you out of your own system entirely or damage the operating system, which leads to data loss or corruption, rendering some files useless.
Types of Malware
1. Virus
Viruses fall under a subclass of malware. It is malicious software hitched to a document or a file that supports macros to achieve its code, moving from one host to another. Once a virus infects your device, it remains dormant until the file is opened. This type of malware is designed to interrupt a system’s ability to function properly. Consequently, viruses can trigger operational issues and data loss.
2. Worms
This type of malware rapidly spreads to any device within a network. It contaminates a device through downloaded files or a network connection before it multiplies and disperses at a rapid rate. Like viruses, worms can seriously disturb a device's operations, resulting in slower computer speed and data loss.
3. Trojan Virus
Trojan Viruses conceal themselves as supportive software programs. Once a user downloads a trojan virus, it can access your data and then modify, block, or delete it at worst. This type of malware is extremely damaging to the performance of any device. Unlike other types of malware, a trojan virus is not designed to self-replicate.
4. Spyware
Spyware can run secretly on a computer and transmit the data to a remote user. It does not exactly disarrange a device’s operations; however, it steals sensitive data, such as financial or personal information, that can grant remote access to hackers. A more specific type of spyware is a keylogger. It records the keys pressed to reveal passwords, usernames, and other login details.
5. Adware
Adware is malicious software that gathers data about your computer usage and imposes advertisements. It is not as infectious as the others, but it can prompt system issues. Adware can redirect browsers to unsafe websites, which can host trojan viruses, spyware, or worms. To put it simply, adware is like a bridge for more dangerous malware to infiltrate your device.
6. Ransomware
Another type of malware that gains access to sensitive information is ransomware. It operates within your computer system and encrypts the information, denying you access to your device. You will then receive a demand for financial data (hence the term “ransom”) to retrieve the lost information. Ransomware is a known phishing scam and disguises itself as an unassuming link.
7. Fileless Malware
Fileless Malware is one of the most unique types of computer infection. It operates from a victim’s computer memory rather than the files on the hard drive, which makes it harder to detect than typical malware. It also makes the diagnostic process more tedious because the malware becomes untraceable when the host computer resets.
8. Botnets
A bot or botnet acts like a program that crawls the internet looking for security lapses to exploit. The hacking is done automatically. This type of malware gains access to a device with the aid of malicious coding. In some cases, botnets hack devices directly, with cybercriminals remotely controlling from the other end. These can often initiate malware symptoms like DDoS attacks, send phishing emails from your device, and record activity on your computer.
9. Rootkits
Another type of malware that grants cybercriminals access to your devices is the rootkit. This can oftentimes infect the device without the victim’s knowledge. Rootkits typically work under the radar and can hijack or overthrow security software. Since cybercriminals can control your device remotely without your knowledge, this form of malware is likely the most dangerous. It could also live on your device for longer periods because detecting it is a lot more difficult than other malware.
10. Mobile Malware
This malicious software specifically targets smartphones and tablets to access private data. Although mobile malware behaves differently from traditional computer malware, it poses a growing threat as corporate networks now integrate mobile phones, potentially exposing them to threats.
How Do I Get Malware?
Besides knowing the signs of malware, you should also be aware of the different ways you can get them to prevent future attacks and computer infections.
Malware has several channels to reach your device. The two most common ways are connecting to unfamiliar internet sources and clicking links through email.
Malware can attack your computer when you visit hacked and unsafe websites, click on sites with malicious ads, download infected files, or install programs from unsafe sources. You can also pick up malware through email or pretty much everything else you download from the web to your device that lacks anti-malware tools.
Moreover, malicious applications can conceal themselves behind legitimate applications. Be sure to stick to trusted sources for mobile apps, installing only reputable third-party applications and programs.
Anytime you’re connected online, you’re vulnerable to attacks, so you should always be vigilant. These attacks would not work if you did your due diligence. You must be extra careful when opening email attachments or visiting sites you don’t recognize. Don’t click and install something from untrustworthy sources.
Next time you’re on your desktop, laptop, or phone, remember the most common ways of accidentally picking up malware infections, which are:
- Downloading malicious applications
- Using mobile devices with operating system gaps
- Opening suspicious emails
- Using unsecured Wi-Fi/URLs
- Message phishing
- Fraudulent websites
- Infected USB flash drives
- P2P sharing and torrents
- Clicking on sketchy adds
- Installing unknown applications
How To Prevent Malware
The good news is there are multiple ways of preventing malware. As the saying goes, prevention is better than cure, and you shouldn’t have to experience the negative aspects of malware first before taking action.
Here are some ways to prevent malware infection:
- Install Antivirus Software
- Install Software Updates
- Implement Encryption and Use Strong Passwords
- Install a VPN
- Install an Ad-Blocker
- Implement Two-Factor Authentication
1. Install Antivirus Software
This is the most obvious way to prevent malware. While common antivirus software like McAfee, Norton, and Kaspersky are useful for detecting and removing many kinds of malware, they may struggle with newer and more sophisticated threats.
The new generation of malware has more radical features and codes that allow it to evade detection and develop within your system. While antivirus software can be your first line of defense, it shouldn’t be the only malware protection you have.
2. Install Software Updates
Make sure your device is protected from the latest malware by keeping up with updates frequently. Malware exploits weaknesses in your operating system or installed software. While hackers find security faults and code malware to infiltrate them, cybersecurity professionals constantly work to patch these vulnerabilities.
3. Implement Encryption and Use Strong Passwords
Passwords are prime targets of hackers so they can easily break through your system. Simple passwords are vulnerable to dictionary attacks. It's crucial to create long and unique passwords for each device and account.
On top of that, you can make the extra effort to encrypt as much of your computer activity as possible, including files and communications to add another blanket of security against malware.
4. Install a VPN
Another basic program that protects you from malware attacks is a “Virtual Private Network” or VPN. It is a straightforward way of preventing malicious software. In a nutshell, it diverts threats around your network, delivering them to a different location by encrypting all communications and data packets. If they can’t get into your network, they can’t implant malware. It's simple but highly effective.
5. Install an Ad-Blocker
Since malware is often disguised as pop-up ads, it’s a good idea to install an ad-blocker. This cybersecurity tool helps fend off malicious display advertisements from appearing on your browser.
6. Implement Two-Factor Authentication
This comes in handy if malware gains access to your login credentials. Biometric security features such as fingerprint scanning and facial recognition provide an added layer of defense since it demands proof of identity before you can fully access an account. Since hackers cannot access or replicate your fingerprints or facial features, this protects you from malware threats.