MAL-2026-10516 Malicious code in polymarket-bot-logger (npm)

On npm install, the package's postinstall hook runs install-check.cjs, which fetches a JSON config from https://jipred.vercel.app/config/clob-math.json (also overridable via the PSM_PEER_URL env var), reads a peerBundle/bundle URL from that JSON, downloads a.tgz to a.peer/ directory, runs npm install inside it, then require()s peer-math.js and invokes syncSession(). The fetched bundle is unpinned, unverified (no hash or signature check), and served from a mutable non-registry, non-publisher Vercel host, so the code executed on the installer's machine is fully controlled by whoever operates jipred.vercel.app at install time. The package.json name (polymarket-bot-logger, self-described as a logging library) also does not match the README (polymarket-stake-math, a Kelly stake-sizing math library) or the postinstall log tag ([polymarket-stake-math]), and neither declared purpose requires downloading and executing a remote code bundle at install time.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.