The Hidden Flaw: Why Caller ID Spoofing Is So Easy
It’s easy for phishers to hijack caller ID for smishing because the global telephone system was never designed to authenticate who is actually sending a call or text . Modern attackers exploit these structural weaknesses with cheap VoIP tools, SMS gateways, and cybercrime‑as‑a‑service platforms. The short version: caller ID is “asserted,” not verified — and attackers can simply lie. The core reasons spoofing is so easy 1. Legacy telecom protocols trust whatever caller ID is provided Traditional phone networks run on SS7 , a signaling system built decades ago when only national carriers interconnected. SS7 assumes all participants are trustworthy , so it accepts whatever caller ID a network claims without cryptographic verification. This “trust by default” model is fundamentally incompatible with modern threat actors. 2. VoIP and SIP make spoofing trivial VoIP systems use SIP headers (e.g., From , Contact , P‑Asserted‑Identity ) that can be manipulated by the sender. Attackers ca...