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With our increasing reliance on our phones, computers, and other internet-connected technology and accessories, security is more important than ever. To be able to recognise when our tech might be compromised can save you from potential catastrophic losses. It’s therefore important to be on the lookout for computer malware signs.
How often do you pay for something using your credit card or online wallet? How many passwords do you have saved or “remembered” so you can quickly log in? Hackers can gain access to your devices in numerous ways, but in many instances, it’s not immediately apparent.
The Current State of Internet Security
According to the Symantec 2017 Internet Security Threat Report (ISTR), 1 in every 131 emails you receive is infected with malware. Opening such an email infects your computer and gives attackers access to your personal and business data.
In a business environment on a company network, this can give hackers access to the same shared systems and folders that your computer has access to, leading to a data breach with far-reaching consequences. All it takes is for a high-level executive, member of the C-suite, or HR personnel with access to sensitive records to click that infected email and it’s game over for some businesses.
Being aware of the dangers and spotting the computer malware signs is, therefore, more important than ever to prevent the disastrous effects of a successful cyberattack. These are the warning signs of a possible data breach and that your system has been infected.
20 Computer Malware Signs To Be Aware Of
1. Pop-Ups
Very often, malware and viruses will be disguised as regular notifications. Your computer will display the notification, often saying that your PC is infected and offering help to remove the threats. If you accept “help,” you will be prompted to visit a website and leave your credit card information to pay for the service of removing the threat. Even though such an attack pattern is not new and has been present for a while, people still fall for it very often. This is the most common of all computer malware signs.
2. Sudden Sluggish Performance
If you notice that your computer is slower than usual, the first thing to do is check the Task Manager. You can access it by simply writing “Task Manager” after hitting the Windows key on your keyboard.
Once there, check the Performance tab to see whether any of your hardware is being used too much: the CPU, memory, disks, or GPU. Chances are, your memory might be compromised by malware.
If you’re not infected and your computer is still slow, check out our course here to improve computer performance.
3. Has a Mind of Its Own
Some glitches in your system might appear like your computer has a mind of its own – usually a brief glimpse of a registry change or your mouse moving by itself. In most cases, these are just little glitches – a speck of dust on the mousepad, for instance. But this could also be one of the computer malware signs. If mouse movements are deliberate and make sense, like the mouse moves and opens or closes applications, then you are definitely dealing with a far more serious threat than a dusty mouse pad.
To disable this kind of remote access, the first thing you should do is disconnect your PC from the internet, disable network drivers so it can’t connect again, and make sure any connectivity options are disabled, e.g. Bluetooth. Then, you can start dealing with removing the issue.
4. Crashing
Your computer might crash for no apparent reason. Often, software and hardware incompatibility are to blame, but if this is excluded, computer malware infection is a real possibility. To see what the crash was caused by, go to Event Viewer by hitting the Windows button on your keyboard and writing “Event” – it should be suggested as the first option. Once opened, go to Windows Logs and go through those that are marked as an error. This will give you more insight into what caused the crash and help you or your IT team find a solution fast.
5. Low storage
If your computer is suddenly running low on storage, it might be that you have not been paying attention to how much you have left. Some malware and viruses, however, are programmed in such a way that they replicate endlessly until they use up all the storage space you have.
Always ensure you know how much space you have left. If you know for sure that your hard drive partitions had more than enough, suspicious activity is to be expected.
6. You Don’t Appear to Have Security Measures Working, e.g. No Antivirus etc.
Your computer might notify you that your security isn’t working – that your antivirus has been disabled. If this is the case, check the status of your antivirus immediately. While this can be a system glitch while your antivirus is updating, it is often a sign that you were infected.
If you can’t get your antivirus software up and running, you will have to either install a new antivirus and antimalware software or, if you’re using a paid version, contact your antivirus manufacturer’s support and let them lead you through the recovery process.
7. Ads
Malware software can also cause pop-up ads, new tabs in browsers, or change homepages, and search engines, without the user’s consent. To get rid of these annoying pop-ups and ads, you will have to find the infected software and remove it from your device.
8. New Icons on Your desktop
If you notice a new icon on your desktop that you don’t know the origin of, suspect foul play right away as new icons are computer malware signs. Malicious software might be installed on your device, threatening to steal your credentials, cause havoc, or even lock you out. If this is your work computer, contact your IT department right away as it could have been installed on the network, not just your own device.
9. Corrupted folders or Missing folders
If you get a prompt your file is corrupt or you realise some folders are missing from where they are supposed to be, it could be an infection. Some malicious software will not be after your credit card data – the intent can simply be to erase all your data from your drives. While this is less of a threat today than it was before thanks to various online storage solutions, not all your data is stored online. If you have lost files, a system restore might be a way of getting them back.
10. Ransoms
Some malware acts as a simplified version of ransomware by locking you out of your computer until you pay. But, unlike hardcore ransomware, there are some things you can usually do to unlock it.
Using Windows safe mode might do the trick. Once you have booted Windows that way, you can run a virus scan and remove the ransomware. There are also dedicated ransomware removal tools from established antivirus brands, and even Microsoft itself has tools available. Another option is to use System Restore to restore your computer to a version that wasn’t infected yet.
11. Errant Messages
Your system might notify you that an application requires permission to do something, for example an application trying to change something on your computer or connect to the network. This usually happens when you start up, update or install a new application. However, if none of these have happened recently and you’re still getting the messages, your PC might be infected.
12. Redirecting Web Browsers
If you notice that your browser started redirecting you to random sites, you might be dealing with a browser redirect malware, whose aim is to use these redirects to artificially boost traffic to such sites, gather search data, or to try to scam users and steal their personal data. Search for suspicious programs on your device if you suspect this to be the case.
13. New Home Pages
If you open your web browser and your homepage is changed, you need to check which program might have caused this. Usually today, a lot of software will come with additional taskbars or options to change your homepage while you install them. You can opt out of it easily during installation, but many people oversee this. While such changes and additions might not be viruses themselves, they often lack proper security and can easily be used as a point of entry.
14. You’re (Not) Reaching Out
You might find that new conversations are popping up in your email inbox or social media that were started by ‘you’, but you can’t recall starting them.
These spam messages encourage your contacts to click on links that will then infect them. A popular scam is the malware will send an SOS email or message saying you’re stranded and need cab money or a train ticket. It might not seem like a lot but if every one of your friends and every one of their friends become infected, it’s a lot of potential.
15. BSOD – Blue Screen, Will Not Boot
If your computer suddenly becomes unresponsive and you see the dreaded blue screen of death (BSOD), it could be malware.
However, BSOD often happens after you install new software or hardware. Check whether you have the latest drivers installed for all your components and search for possible incompatibility between programs and hardware you are using.
If this is not the case, you will have to consult the Event Viewer again to see what exactly caused the BSOD.
16. Credit or Bank Purchases
If you get notified that there were purchases made with your credit card, or money was taken from your bank account but you didn’t do it, ask your bank to verify how payment was made. If it was done using your card (not in person) it means it was an online transaction. This can mean your device is compromised and they’ve taken the details, particularly if you have them saved e.g. Google online.
Cancel your cards, disconnect from the internet and do a thorough sweep of your devices to make sure that the breach didn’t come from them.
17. You can’t login to your accounts
If you can’t get access to your account because your password suddenly isn’t working, there’s a good chance you’re dealing with a case of account theft. This is already one of the serious computer malware signs. Always have a fallback option for such cases – a way to reset your password via your phone number, for instance. To minimise such a risk, have two-factor authentication that will request a code sent to your phone or a generated code from an app installed on your phone.
If you get a notification from your authenticator, for example, a code on your phone but you’re not trying to log in, check your system for malware and change your passwords immediately. It could be someone with a keystroke logger.
18. Your Hard Drive Appears to Be Constantly Working Even When Doing Nothing
Erratic and sluggish operations can be caused by a lot of software and hardware issues. To see what is happening, you will have to open your Task Manager by hitting your Windows key button and typing “task manager” for it to appear on the list.
Once opened, look at the performance of your hardware. If you see that your disk is on ‘100%’ most of the time, you will have to check which processes are running and might have caused this. Note that certain Windows processes might cause this from time to time – recently microsoft.photos.exe, a legit Microsoft application, was causing this issue for some users.
If you find any other applications that are unfamiliar to you and are using your disk fully, terminate the process by right-clicking on it and selecting the “End Task” option. Find which program the task belongs to in order to see whether it’s a real malware or virus issue or just an incompatible program.
19. File Names Change or Are Missing
Any changes to files – either the names or the location of the files – should immediately be attributed to malicious software activity. A deep scan with a dedicated software will be needed to find the infection. Any files that were affected – renamed, deleted, or removed – might be beyond saving, so always make sure you have your data securely backed up online.
20. Unusual login pages
Any changes to login pages you often use – either for work or personal – should be deemed suspicious. Usually, changes like this are announced in advance, so check for news about the changes before you log in. Any pages that require your work, Google, or social media account credentials (both username and password) for login should also be avoided as these might be phishing sites that are trying to steal your credentials.
If you’ve navigated to the page through an email, close the tab and go to the company you’re trying to login to directly. If you don’t recognise the site, NEVER give your credentials away!
It’s important that if you feel there is something wrong with your computer, particularly if you are on a company device or part of a shared network that you report it! Small and subtle changes can lead to big data breaches and catching malware early is key.
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