State-Backed Hackers Target Military Officials and Journalists on Signal in Latest Cyberattack

German security agencies warn of a likely state-sponsored espionage campaign targeting military officials, diplomats, and investigative journalists across Europe by abusing legitimate Signal features. Attackers use two social-engineering techniques — fake “Signal Security Support” messages requesting six-digit PINs or SMS codes to register victims’ numbers on attacker devices, and QR-code device linking to silently sync and read up to 45 days of messages — enabling account takeover or persistent stealth access; officials advise checking Linked Devices, enabling Registration Lock, and never sharing verification codes.