Supply-chain threat intelligence
Risk score
92
Indexed incident for @velkov/isows (npm).
Package is published as @velkov/isows while its README, repository (wevm/isows), description ("Isomorphic WebSocket"), and author (jxom.eth) impersonate the legitimate isows package. The legitimate upstream utils.ts is an 8-line getNativeWebSocket helper; in this package, _cjs/utils.js and _esm/utils.js append ~50KB of obfuscator.io-style payload (rotated string array a4(), base64+RC4 decoder a5(), debugger-trap class, while(!![]) loops). The payload runs at top level whenever the package is required or imported (the package.json main is ./_cjs/index.js, which loads ./utils.js). Behavior: re-execs Node with a sentinel env var, dynamically loads https/fs/os/child_process/path/crypto, issues an HTTPS GET to an RC4-decoded host/path, streams the response to a hostname-derived filename under os.tmpdir(), validates a sha256 from a sidecar JSON fetched from the same attacker-controlled host (attacker controls both payload and verification), AES-256-GCM-decrypts the bytes with a key XOR-derived from four embedded 32-byte buffers, chmods 0o755, and spawns the binary {detached:true, stdio:'ignore', windowsHide:true} so it survives the parent process. Error-handling stubs are empty to suppress diagnostics. This is the canonical typosquat-plus-dropper supply-chain attack pattern: any installer or transitive consumer that loads @velkov/isows runs attacker-controlled native code on their machine.
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