FBI and CISA Flag Russian Cyber Operations Targeting Select Individuals via Signal

FBI and CISA warn of a Russian intelligence-linked phishing campaign targeting Signal users — especially high-value U.S. officials, military personnel, political figures, and journalists — in which attackers impersonate support channels to trick victims into sharing SMS verification codes or scanning malicious QR codes to link attacker devices and take over accounts; the advisory reports thousands of compromises and recommends never sharing codes, auditing linked devices, avoiding unsolicited QR codes/links, and enabling disappearing messages.