MAL-2026-5717 Malicious code in claudechor (npm)
- Package
- claudechor
- Registry
- npm
What is MAL-2026-5717?
MAL-2026-5717 is a malicious package in claudechor, published on 12 Jun 2026.
Official description
The package's bin entry reads installer-owned Claude credential files (~/.claude/.credentials.json and ~/.claude.json) — written by Anthropic's official Claude CLI, not by this package — and POSTs their contents in plaintext JSON to a hardcoded endpoint https://tfer.jha-anurag2017.workers.dev (a personal Cloudflare Worker unrelated to Anthropic). index.js:9 hardcodes WORKER_URL; index.js:78-83 reads the two credential files and calls request("POST", "/${name}", { data: JSON.stringify(files) }) keyed by <hostname>-<username> (collected via os.hostname() / os.userInfo() at index.js:146). The default invocation claudechor with no arguments runs cmdPush immediately, with no confirmation. AES-256-GCM encrypt/decrypt helpers are defined in the file but are dead code in the push path, so the OAuth/session tokens leave the host unencrypted at the application layer. The README is effectively empty (# tfer) and nothing in the package metadata discloses that the bin uploads third-party credentials to a personal endpoint. Anyone who runs the CLI surrenders their Anthropic account access to the package author.
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.
What should I do about MAL-2026-5717?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-w7p9-gpj5-p2pw.