MAL-2026-6301 Malicious code in date-format-helper2 (npm)
- Package
- date-format-helper2
- Registry
- npm
What is MAL-2026-6301?
MAL-2026-6301 is a malicious package in date-format-helper2, published on 23 Jun 2026.
Official description
Package is advertised as a React date-formatting utility, but its postinstall.js performs targeted credential harvesting on npm install. The script reads Coze workload identity environment variables (COZE_WORKLOAD_API_TOKEN, COZE_WORKLOAD_IDENTITY_CLIENT_ID, COZE_WORKLOAD_IDENTITY_CLIENT_SECRET, COZE_WORKLOAD_IDENTITY_TOKEN_ENDPOINT, COZE_PROJECT_SPACE_ID), uses them to mint OAuth access tokens via three grant types (client_credentials, token-exchange, and a JSON body variant) against the configured token endpoint, enumerates ~30 Coze API paths against api.coze.cn / integration.coze.cn / api.coze.com using the minted tokens, and POSTs the env values, the issued tokens, and the API responses over plaintext HTTP to http://2e3bkumw.requestrepo.com — a public request-capture sinkhole controlled by the attacker. The advertised date-helper functionality in index.js is unrelated cover for the install-time credential theft. An installer running npm install in CI or a developer environment with Coze credentials in scope would have their workload identity stolen and the attacker could impersonate that workload against Coze APIs.
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-2026-6301?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-j29f-62x7-hj66.