What was done
Fedele Mantuano had Codex analyse a MalwareBazaar loader statically in a no-network Docker lab. The report covers its structure, destinations and limits.
A MalwareBazaar sample first labelled an infostealer was analysed statically with Codex, REA and Ghidra. The evidence supported calling it a loader, not a stealer, and the write-up marks what is known and what depends on payloads that were never obtained.
How it was done
Codex was asked to use REA to inspect the executable inside a prepared Docker lab with no network access and the sample mounted read-only. It was told not to run the malware, use Wine or contact any endpoint. The 98 MB Windows executable embeds a Bun runtime and a JavaScript bundle, so the work focused on the extracted 345 KB bundle. Obfuscation (string tables, RC4, Base64, XOR) was decoded with analyst-written decoders, and some values were checked against an independent Python implementation.
Results
The report describes system and environment checks, encrypted reporting, payload download and decryption, in-memory loading and a "miner" branch. It lists hardcoded and fallback server destinations and found no domain generation algorithm. It also separates what the code says from what was observed. No dynamic confirmation was done, and missing remote components limit the conclusions.
