Whoscall warns of phone scams using fake international dialing codes

Whoscall has issued a warning regarding fraudulent international calls using non-existent dialing codes, specifically those starting with “+422” or “+42”. While “+42” was historically used by Czechoslovakia, it is no longer a valid current country code; modern codes for the region are “+420” for the Czech Republic and “+421” for Slovakia.

These fraudulent numbers are made possible through caller ID spoofing. Due to the architecture of traditional Public Switched Telephone Networks (PSTN) and the rise of Voice over Internet Protocol (VoIP), the caller ID field often lacks rigorous verification, allowing scammers to input arbitrary numbers.

Experts warn that even if a call is answered and immediately disconnected, it may be a tactic to test whether a phone number is active. Answering or calling back can flag the number as a valid target for future scams or harassment. Users are advised to avoid answering unknown international numbers with suspicious prefixes and to never call back unrecognized digits.