The Federal Bureau of Investigation (FBI), National Security Agency (NSA), US Cyber Command, and international partners are releasing this joint Cybersecurity Advisory (CSA) to warn of Russian state-sponsored cyber actors’ use of compromised Ubiquiti EdgeRouters (EdgeRouters) to facilitate malicious cyber operations worldwide. The FBI, NSA, US Cyber Command, and international partners – including authorities from Belgium, Brazil, France, Germany, Latvia, Lithuania, Norway, Poland, South Korea, and the United Kingdom -- assess the Russian General Staff Main Intelligence Directorate (GRU), 85th Main Special Service Center (GTsSS), also known as APT28, Fancy Bear, and Forest Blizzard (Strontium), have used compromised EdgeRouters globally to harvest credentials, collect NTLMv2 digests, proxy network traffic, and host spear-phishing landing pages and custom tools.