About three months ago, my computer was infected and I lost access to several accounts. While researching what happened, I read that some malware can spread across a local network, infect routers, or reach other devices. I installed Kaspersky on the computer, but I'm still worried that another device—or the router itself—could be compromised and reinfect everything. I also downloaded a ZIP file for a mobile game modification on my phone, then factory-reset the phone. Since then, I've repeatedly logged into the router's administrator panel from both my computer and phone to check for suspicious settings, and I'm worried I may have accidentally created a security hole. I even replaced the router. There haven't been any clear ongoing symptoms, aside from internet connection problems around the time my accounts were compromised, which stopped after switching routers and internet providers. Should I take any additional steps, such as reinstalling the computer's operating system or resetting the phone again? Does replacing the router meaningfully help, and how concerned should I be about malware such as router-targeting trojans or network worms spreading to my other devices?
2 Answers
A router from around 2019 or 2020 is not automatically unsafe, but it should have received firmware updates. Since you already installed a new router, update it immediately, reset it to factory defaults if needed, configure it manually, and check that remote management and unnecessary services are turned off. Logging into the administrator page from your phone or computer does not itself create an opening for malware; the concern would be an already-compromised device or an exposed router service. Also review the router’s connected-device list and wireless password, but try not to keep repeatedly checking unless you find a concrete warning sign.
If the computer was compromised, the safest thorough fix is a clean operating-system installation from trusted USB media rather than relying only on a normal reset. A factory reset generally removes apps and user data from a phone, so it is usually enough for ordinary malware, especially if the phone is not rooted. After cleaning the devices, update their software, change important passwords from a known-clean device, enable two-factor authentication, and avoid reusing passwords. Replacing every piece of network equipment is usually unnecessary; widespread router infections are uncommon and are more often associated with outdated firmware, exposed administration interfaces, or targeted attacks. Make sure the new router is updated, use a strong unique administrator password, disable remote administration, and use modern Wi-Fi security.
The internet outages by themselves don’t prove that malware was spreading. Since they stopped after changing providers and the router, an ISP or hardware problem is at least as plausible. If there are no continuing account takeovers, strange router settings, unknown devices, or malware detections, there probably isn’t evidence of an ongoing network infection.