This seems to be the only source for this information, while on the other hand I'm seeing this;
Wired: A Signal Update Fends Off a Phishing Technique Used in Russian Espionage
Google warns that hackers tied to Russia are tricking Ukrainian soldiers with fake QR codes for Signal group invites that let spies steal their messages. Signal has pushed out new safeguards.
This seems to be the only source for this information, while on the other hand I'm seeing this;
Wired: A Signal Update Fends Off a Phishing Technique Used in Russian Espionage