When netstat Lies: Detecting eBPF Magic-Packet Backdoors on Linux
A clean netstat is not proof of safety: eBPF backdoors like LinkPro keep an internal listener, rewrite ports through XDP/TC, and can make bpftool lie about themselves. The durable signal is the bpf() syscall at load time, and on Cilium-heavy fleets, telling real loaders from noise is most of the work.