SIM card theft refers to the unauthorized acquisition or use of someone else’s Subscriber Identity Module (SIM) card without their knowledge or consent. SIM cards are small, removable cards used in mobile devices to store information such as the user’s mobile phone number, contacts, and authentication data required for network access.
The theft of a SIM card can occur in different ways:
Physical theft: When a person’s SIM card is stolen along with their mobile device. This can happen through pickpocketing, robbery, or if the device is left unattended and accessible.
Social engineering: Some individuals may use deceptive techniques to trick mobile network operators into transferring a victim’s phone number to a different SIM card under their control. This method is known as SIM swapping or SIM hijacking.
Once an individual gains unauthorized access to someone else’s SIM card, they can potentially misuse it for various fraudulent activities, including:
Making unauthorized calls or sending text messages using the victim’s mobile number, which can result in financial losses for the victim.
Gaining access to the victim’s personal information stored on the SIM card, such as contacts, messages, or call history.
Bypassing two-factor authentication (2FA) systems that rely on sending verification codes via SMS to the victim’s mobile number. This can enable the thief to gain unauthorized access to the victim’s online accounts.

If you suspect that your SIM card has been stolen or compromised, immediately contact your mobile network operator to report the incident and request appropriate actions to secure your account.