There’s a popular stereotype that Apple’s computers are largely immune to malware. Not only is is that incorrect, it appears that sophisticated hacker(s) might have been toying with the idea of a heist or drop nasty enough they’d have needed to cover their tracks. As Ars Technica reports, security researchers at Malwarebytes and Red Canary discovered a mysterious piece of malware hiding on nearly 30,000 Macs, one designed to deliver an as-yet-unknown payload, and with a self-destruction mechanism that might remove any trace that it ever existed. They’re calling it Silver Sparrow.