The FBI has issued an urgent advisory that will impact many, if not most, home users of the Internet. The specific threat, which is felt to be State sponsored, is known to have infected over a half million home and SOHO router devices.
Specifically, if you own a home or SOHO router or NAS (network attached storage) device made by Linksys, MikroTik, Netgear, TP-Link or QNAP, the advisory recommends rebooted the device as soon as possible. Rebooting will disrupt a portion of the malware. If the malware has already embedded itself in to the device, there may still be a risk after the reboot. To ensure maximum safety, you may wish to perform a factory reset on your device and set it back up with a secure password and wireless passphrase (if your device doubles as a wireless access point) that is different from what you had previously.
While not likely that you, individually, are the target of the hackers, your device may be being prepped to help execute a broader cyberattack that could, theoretically, put your data at risk. An abundance of caution is warranted given the urgency of the FBI advisory. It is also recommended to be sure your device is running the latest manufacturer firmware version and that you disable all Internet accessible remote managment of your device.
You may read the FBI advisory here.