SMiShing, or SMS Phishing, is a form of social engineering used to compromise an individual based on trusted phone numbers. The concept presents an end user with a familiar dialogue that builds your relationship with the goal of extracting information and ultimately some form of financial or information gain. The SMS message may appear to come from a person in your contacts list or from a company you have done business with. The way threat actors gain access to your name could be from a previous breach or from malware that has extracted the contact, or from an SMS list from the source victim’s mobile device. That information is then used to target potential victims and spoof the relationship. Here are a few things to consider if you think you are a victim of a SMiShing attack:
  • Government entities like the IRS or HUD never use SMS text messages for communications. All official and legitimate communications always come through the United States Postal Service.
  • Any SMS text message that asks you to reply to a form or asks for sensitive information is probably fake. Why would a trusted person or company ask you for your full name, address, or any other personally identifiable information, in bulk, through a text message? This is the setup for a scam.
  • If the responses to your skepticism are met with any hostility, it is probably SMiShing. Commonly, threat actors will reply with “Why don’t you trust me?” or “Your friends have had success with me, why would you pass this up?” Real companies and friends do not follow this patterned behavior.
  • Real businesses that use SMS text messaging for actual business typically ask for replies in simple terms. Like, reply “Y” to confirm your doctor’s appointment or “STOP” to terminate the text messages. SMiShing typically will use longer replies to conduct the attack, but be mindful – an attack may use the word “STOP” in the first message just to validate that someone is actually on the other side of the phone and willing to answer.
  • If the SMS message has links that you do not recognize or solicits the installation of new applications, do not click on the link; especially on Android mobile devices. This is a way to potentially install malware or exploit a vulnerability and compromise the device.
SMiShing, like Vishing (voicemail phishing made famous via fake IRS scams), is yet another targeted attack focusing on social engineering and the flaws in the SMS texting system that allow source phone number spoofing. If you want to minimize the risk, outside of spoofed phone numbers, change the settings on your phone to block SMS text messages from users not in your contacts list. Otherwise, it is an education process to look for the threats and not respond.