AN1721: Analytic 1721
From the defender view: a sandboxed process receives/creates a high-entropy Mach-O/bundle or encrypted segment, performs in-memory decrypt/unpack (mmap/mprotect RW→RX or RWX), optionally drops a transient image in app-writable dirs, then loads it through dyld/dlopen or spawns it. We correlate: (1) opaque blob write/arrival → (2) kernel memory protection changes → (3) dyld/dlopen from app-writable path or posix_spawn of a recently created image → (4) (optional) code-sign evaluation anomalies for the new image.
