A previously undocumented and mostly undetected variant of a Linux backdoor calledBPFDoorhas been spotted in the wild, cybersecurity firm Deep Instinct said in a technical report published this week. “BPFDoorretains its reputation as an extremely stealthy and difficult-to-detect malware with this latest iteration,” security researchers Shaul Vilkomir-Preisman and Eliran Nissan said. BPFDoor (