The npm package 'contract-contract-builder' version 35.5.2 contains malicious code that downloads and executes a platform-specific binary from dynamically assembled Cloudflare Workers hosts. This binary is saved to temporary directories with disguised filenames, given executable permissions, and launched detached from the main process. If HTTPS delivery fails, a DNS TXT record fallback channel reconstructs a base64 payload from multiple DNS TXT records. The package falsely advertises itself as a UI toolkit, but the fetched binary is unrelated, unverified, and executed automatically upon import.