QRishing: The Susceptibility of Smartphone Users to QR Code Phishing Attacks

The matrix barcodes known as Quick Response (QR) codes are rapidly becoming pervasive in urban environments around the world. QR codes are used to represent data, such as a web address, in a compact form that can be readily scanned and parsed by consumer mobile devices. They are popular with marketers because of their ease in deployment and use. However, this technology encourages mobile users to scan unauthenticated data from posters, billboards, stickers, and more, providing a new attack vector for miscreants. By positioning QR codes under false pretenses, attackers can entice users to scan the codes and subsequently visit malicious websites, install programs, or any other action the mobile device supports. We investigated the viability of QR-code-initiated phishing attacks, or QRishing, by conducting two experiments. In one experiment we visually monitored user interactions with QR codes; primarily to observe the proportion of users who scan a QR code but elect not to visit the associated website. In a second experiment, we distributed posters containing QR codes across 139 different locations to observe the broader application of QR codes for phishing. Over our four-week study, our disingenuous flyers were scanned by 225 individuals who subsequently visited the associated websites. Our survey results suggest that curiosity is the largest motivating factor for scanning QR codes. In our small surveillance experiment, we observed that 85% of those who scanned a QR code subsequently visited the associated URL.