SIM Swap
Definition
Fraud pattern where the attacker convinces the telco to port the victim's MSISDN to a SIM the attacker holds. Once active, the new SIM receives all SMS OTPs, letting the attacker reset banking, wallet and email credentials. TRAI mandates a 24-hour OTP cool-off after any SIM swap.
- Mechanism
- Attacker ports victim's mobile number to a SIM they control
- Primary target
- SMS one-time passwords (OTPs)
- India safeguard
- TRAI mandates a 24-hour OTP cool-off after a SIM swap
- Downstream harm
- Banking, wallet and email account takeover
Common questions
What evidence do investigators pull to prove a SIM swap occurred?+
Telecom porting request logs, call detail records showing the sudden loss of service on the victim's original SIM, and the KYC documents submitted for the fraudulent port are the core evidence trail linking the swap to a suspect or outlet.
Does the 24-hour OTP cool-off fully prevent SIM swap fraud?+
No, it only blocks OTP-based transactions in the first day after a swap; an attacker who already has other authentication factors, such as a phished password, can still act during that window through channels that do not rely on SMS OTP.
Related terms
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- IMSI Catcher
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- Phreaking
- Tone-based exploitation of the public switched telephone network, pioneered in the 1960s and 1970s. The 2600 Hz tone, generated by a toy...
- QRJacking
- Physical replacement or overlay of a legitimate merchant QR (typically a UPI QR at a shop counter) with a fraudster's QR pointing...
- TRAI 24-Hour Cool-Off
- Telecom Regulatory Authority of India directive (2018 and tightened thereafter) requiring that after a SIM swap the new SIM cannot be used...