"When unsuspecting buyers click checkout on compromised stores, a malicious script intercepts the click & displays a fake 'Secure Checkout' overlay that includes card details fields & a billing form" https://www.bleepingcomputer.com/news/security/hackers-use-pixel-large-svg-trick-to-hide-credit-card-stealer/
Hackers use pixel-large SVG trick to hide credit card stealer

A massive campaign impacting nearly 100 online stores using the Magento e-commerce platform hides credit card-stealing code in a pixel-sized Scalable Vector Graphics (SVG) image.

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