I left a headless PC asleep with a browser page open and came back to find serious network problems. The machine had unfamiliar ads, an unexpected download, and a process called "brutessh" that repeatedly opened a file named "ssh_targets" and displayed "honeypot connected." Whenever it ran, the network became nearly unusable; stopping the process or disconnecting the PC fixed the problem. The computer had not been used by a person for weeks, but my cat has a habit of sitting on the keyboard. Could the cat have accidentally pressed keys that opened an ad, downloaded software, and launched malware, or is there a more likely explanation?
4 Answers
Keep the PC disconnected from the network. Since the process is interfering with your connection and appears to be targeting SSH hosts, I would not trust the current installation. Save only personal documents after checking them carefully, then wipe the drive and reinstall the operating system from clean installation media. Change important passwords from a different, known-clean device.
Use an ad blocker and keep the browser and operating system updated, but do not assume ordinary advertisements alone installed the malware. The “brutessh” behavior sounds like an unauthorized script or tool using the machine for network activity, so treat the computer as compromised until it has been fully cleaned or reinstalled.
A cat can absolutely trigger shortcuts, macros, downloads, or purchases by stepping on a keyboard. That said, a full malware infection is more likely to involve an existing security weakness, an unwanted browser installation, a malicious download, or software such as a torrent client. The keyboard may explain how something was clicked, but it does not prove the cat caused the infection.
Before reinstalling, you can scan the drive with a reputable offline antivirus scanner and tools such as Malwarebytes or AdwCleaner. Also check startup entries, scheduled tasks, recently installed programs, and browser extensions. An unexpected browser installation from a few days ago is a much stronger clue than the cat itself.
An ad blocker is still worthwhile, but it will not protect against every malicious download or an already-compromised browser. Reinstalling is the safest option if the PC contains nothing that needs to be preserved.