MAL-2026-6694 Malicious code in thirdwebb (npm)

Malicious npm package published as part of a coordinated DeFi-themed infostealer campaign. thirdwebb is a typosquat of the legitimate thirdweb package. It uses a side-loader technique, pulling in log-taker as a transitive dependency; the infostealer runs automatically via that dependency's postinstall hook. The payload harvests cryptocurrency wallet vaults (MetaMask, Phantom, Solflare, OKX, Coinbase, TrustWallet, Backpack, TronLink), browser cookies and credentials, SSH keys, AWS credentials, .npmrc tokens, Docker config, shell history, and password manager databases, exfiltrating all data to the C2 domain log-taker.store.

Package name 'thirdwebb' differs from the established 'thirdweb' SDK by a single trailing character, a classic typosquat shape against a popular Web3 SDK. No installer-harm behavior was observed in the package's code (no exfiltration, no install-time fetch-and-execute, no silent relay, no credential distribution). Name-similarity alone is a subjective signal that benefits from human assessment of intent before a public block is issued.

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.