Signs Your Computer May Be Infected with Malware and What to Watch for in 2026
- jason15065
- Dec 27, 2025
- 4 min read
Malware infections remain one of the biggest threats to business users in 2025. Knowing how to spot signs your computer may be infected is essential for protecting sensitive data and maintaining productivity. This article explains what malware is, highlights the most common infections found today, and offers practical advice on finding the virus. It also looks ahead to 2026, exploring how AI is reshaping IT risks and what to expect in the near future.
What Is Malware?
Malware, short for malicious software, refers to any software designed to harm, exploit, or gain unauthorized access to a computer system. It includes viruses, worms, trojans, ransomware, spyware, adware, and more. Malware can disrupt operations, steal sensitive information, or take control of devices without the user’s knowledge.
Business users face constant risks from malware because attackers often target valuable data, financial information, and intellectual property. Understanding malware types helps in recognizing infection signs and responding quickly.
Common Malware Infections in 2025
The landscape of malware continues to evolve, but several types remain prevalent in 2025:
Ransomware
This malware encrypts files and demands payment for their release. It often spreads through phishing emails or compromised websites. Ransomware attacks on businesses have increased by over 30% in the past year, causing costly downtime.
Trojan Horses
Trojans disguise themselves as legitimate software but carry harmful payloads. They can open backdoors for hackers or install additional malware.
Spyware
Spyware secretly monitors user activity, capturing keystrokes, passwords, and browsing habits. It often arrives bundled with free software or through malicious ads.
Cryptojackers
These programs hijack computer resources to mine cryptocurrency without consent, slowing down systems and increasing energy costs.
Fileless Malware
Fileless malware operates in memory without leaving files on the hard drive, making it harder to detect with traditional antivirus tools.
Adware
While less dangerous, adware bombards users with unwanted ads and can degrade system performance.
How to Spot Signs Your Computer May Be Infected
Finding the virus early can prevent serious damage. Watch for these common symptoms:
1. Slow Performance and Frequent Crashes
If your computer suddenly runs slower or crashes often, malware could be consuming resources or causing conflicts.
2. Unexpected Pop-ups and Ads
Pop-ups that appear outside normal browsing or ads on unusual sites may indicate adware or spyware.
3. Unusual Network Activity
High data usage or unknown connections can signal malware communicating with external servers.
4. Disabled Security Software
Malware often tries to disable antivirus programs or firewalls to avoid detection.
5. Strange Files or Programs
New files or applications you didn’t install could be malware components.
6. Browser Redirects
If your web searches redirect to unfamiliar sites, malware may have altered your browser settings.
7. Unauthorized Access or Changes
Unexpected password changes or account lockouts suggest someone else may control your system.
8. Overheating or Loud Fans
Cryptojackers and other malware that use heavy CPU power can cause hardware to overheat.
9. Suspicious Emails Sent from Your Account
If contacts report receiving strange emails from you, malware may be spreading through your address book.
10. Disabled System Tools
Malware may block access to Task Manager, Registry Editor, or Command Prompt to prevent removal.
Practical Steps for Finding the Virus
Run a Full Antivirus Scan
Use reputable antivirus software to scan your entire system. Many tools now include behavior-based detection to catch fileless malware.
Check Task Manager and Resource Monitor
Look for processes using excessive CPU, memory, or network bandwidth.
Review Installed Programs
Uninstall any unfamiliar or suspicious applications.
Inspect Browser Extensions and Settings
Remove unknown extensions and reset browser settings if redirects occur.
Update Software and Operating System
Keeping software current closes security gaps malware exploits.
Use Malware Removal Tools
Specialized tools can detect and remove threats missed by traditional antivirus.
Monitor Network Traffic
Network monitoring tools can reveal unusual outbound connections.
Backup Important Data Regularly
In case of infection, backups allow recovery without paying ransom.
What to Expect in 2026: AI and the Changing Malware Landscape
Artificial intelligence is reshaping IT security risks in several ways:
More Sophisticated Attacks
Attackers use AI to create malware that adapts to defenses, evades detection, and targets specific users or systems.
Automated Phishing and Social Engineering
AI can generate convincing fake emails and messages, increasing the success rate of attacks.
Improved Defense Tools
Security software uses AI to detect anomalies and respond faster to threats.
Increased Risk of AI-Powered Malware
Malware may learn from its environment, changing tactics mid-attack.
Greater Need for Human Oversight
AI tools require skilled professionals to interpret alerts and make decisions.
Business users should prepare by investing in AI-enhanced security solutions and training staff to recognize new attack methods.
Final Thoughts
As malware threats continue to evolve in 2025 and 2026, the most powerful line of defense isn’t a tool, a firewall, or even AI—it’s the user. Technology can detect, isolate, and respond to threats, but only engaged, informed individuals can stop many attacks before they start. When users stay vigilant, follow safe security practices, and report anomalies the moment they appear, they create a protective shield that no attacker can easily bypass. Empowered users don’t just safeguard their own devices—they protect the integrity of the entire network. Ask Streamline Networks how we can help keep your users involved and diligent about common security attacks.