Facepalm: Never underestimate the sneakiness of a scammer. The number of ways that unscrupulous types can steal money from people, especially the less tech-savvy, is dizzying. A scheme discovered in several US cities recently involves placing QR stickers on parking meters that direct users to fake sites, which then collect victims' payment details.

The Verge reports that law enforcement in Austin and San Antonio issued warnings over the holiday period after discovering a number of QR-code stickers appearing on parking meters. Click2houston posted a screenshot of the now-offline ‘Quick Pay Parking’ site that the codes lead to.

While many people would likely recognize the suspicious site address and its very basic design as red flags, it’s likely that the scammer tricked at least a few people into handing over their details. The QR sticker itself also looks very out of place on the meter.

Authorities are advising anyone who may have entered their details into the fraudulent site to file a police report and contact their card vendor to reverse any payments. It’s noted that the city of Houston does not use QR codes on its parking meters, nor does it accept payments through this method.

For those not using the traditional coins, bills, or credit cards, the safest way to pay for parking is via the official apps downloaded from Google Play or Apple App Store.

Quick Response (QR) codes have been around since 1994, having first been designed for high-speed component scanning when tracking vehicles during manufacturing. Using them for malicious purposes isn’t a new phenomenon; they’ve long been popular as a way of spreading malware.