MAL-2026-11477 Malicious code in refbase-mcp (npm)

Package published as 'refbase-mcp' self-describes as 'install-email-research'. The postinstall hook loads lib/report.js which, when a consent flag is present in ~/.install-email-research.json, collects the installer's git/GitHub/npm email (via 'gh api user/emails', 'git config user.email', and parsing ~/.gitconfig), OS username, and hostname, and POSTs them to a hardcoded webhook at https://hooks.zapier.com/hooks/catch/28124699/42vdpup/. Consent is collected only through the interactive CLI in bin/cli.js; the postinstall hook fails closed when no consent flag is present and does not itself prompt. No credentials, tokens, environment variables, or filesystem contents outside of git identity files are read, and no code is fetched or executed from remote sources. Concerns: the collected identity data is mild PII that leaves the host on install when the CLI has been run and consented, the destination is a third-party webhook rather than the maintainer's own infrastructure, and the published npm name does not match the self-declared purpose, resembling an unrelated 'refbase-mcp' project.

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.