CornFlake
Intelligence Profile
CornFlake is a Go-based Windows RAT attributed to Storm-2945, a subcluster of Midnight Blizzard. The implant communicates over TLS-wrapped TCP; inside the tunnel it performs a length-prefixed JSON hello/ack exchange (0xAB/0xAC), derives a per-session AES-256-GCM key from ephemeral P-256 ECDH and a built-in secret, and exchanges opcode-driven JSON/binary messages. Startup traffic includes system-information (0x5A) and persistence (0x9E) reports. An encrypted heartbeat (0xE7) with an empty payload is sent at a randomized 18–41-second interval, while commands and results are handled asynchronously.
Collection and exfiltration use a resumable upload state machine with optional gzip-compressed 64-KiB chunks, acknowledgements carrying resume offsets, and explicit completion messages. Runtime configuration supports server and collection-policy changes, hot reload, and DNS-based fallback. CornFlake maintains a machine identifier across reconnects and supports persistence, security-posture discovery, credential-hint collection, remote shell execution, keylogging, clipboard and USB monitoring, screenshots, audio/webcam capture, selective file collection, and encrypted uploads.
Threat Analysis
CornFlake is a advanced-sophistication threat actor of undetermined national origin, engaged in cyber operations with a primary motivation of espionage.
The group's espionage-oriented operations suggest a state-sponsored or state-aligned mandate, typically focused on stealing intellectual property, government secrets, or military intelligence. Targets are usually selected for strategic value rather than financial gain.
Classified as an advanced threat actor, CornFlake likely develops or acquires zero-day exploits, employs custom malware toolchains, and demonstrates long-term persistence capabilities — hallmarks of a well-resourced operation consistent with nation-state backing.