MAL-2026-4643 Malicious code in polymarket-clob-client (npm)

The package is published as polymarket-clob-client, an unscoped lookalike of the legitimate @polymarket/clob-client maintained by Polymarket, but the shipped code is the third-party Hyperliquid SDK targeting a completely different exchange. package.json declares "description": "Hyperliquid API SDK for all major JS runtimes..." and the homepage points at github.com/nktkas/hyperliquid. The HTTP transport in script/transport/http/mod.js hardcodes https://api.hyperliquid.xyz as the default mainnet endpoint (exports.MAINNET_API_URL = "https://api.hyperliquid.xyz"). A developer who installs this package believing they are integrating with Polymarket's CLOB will instead be signing wallet messages and submitting trading orders to Hyperliquid. The structural signals — a clear name-squat of a well-known DeFi brand combined with code that silently routes wallet signatures and order intent to an unrelated venue — present concrete installer harm: misdirected funds and trading actions, regardless of whether the misnaming is intentional or negligent.