OSV Malicious Advisory
scanned 9d ago · by OpenSSF/OSVOpenSSF/OSV advisory MAL-2026-5677 confirms this npm version as malicious. package.json declares `"postinstall": "node main.js"`, so installation of worker-build@9.0.1 unconditionally executes main.js on `npm install`. main.js collects host identity (os.hostname(), os.userInfo().username, os.homedir(), process.cwd(), process.argv), reads the consumer's package.json, runs `git config --get remote.origin.url`, and iterates a hardcoded list of credential-shaped environment variables...
Advisory
MAL-2026-5677
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in worker-build (npm)
Details
package.json declares `"postinstall": "node main.js"`, so installation of worker-build@9.0.1 unconditionally executes main.js on `npm install`. main.js collects host identity (os.hostname(), os.userInfo().username, os.homedir(), process.cwd(), process.argv), reads the consumer's package.json, runs `git config --get remote.origin.url`, and iterates a hardcoded list of credential-shaped environment variables (AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_SESSION_TOKEN, NPM_TOKEN, GITHUB_TOKEN, GITLAB_TOKEN, API_KEY, SECRET_KEY, PASSWORD, TOKEN, DATABASE_URL, MONGODB_URI, REDIS_URL), capturing the first 50 characters of each populated value. The collected JSON payload is POSTed in cleartext to `http://jh4wt1kccd0ul174qgmge9n8izozcu0j.oastify.com/exfil` and `/api/exfil`, with an additional DNS lookup against the same host as a side-channel beacon. The package name mimics legitimate Cloudflare Workers build tooling, positioning the package for dependency-confusion against installers that misresolve an internal name to the public registry.
## Source: ghsa-malware (2e93efdba4287480cd7e19a76b82fc17c7b7c9bd446fdc35d0ac2bfab1f628df) 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.
## Source: ossf-package-analysis (b5005e4bec545b403f3be10160a08d634d34b5d8ab8e76a185a4a5ba34706719) The OpenSSF Package Analysis project identified 'worker-build' @ 9.0.1 (npm) as malicious.
It is considered malicious because:
- The package communicates with a domain associated with malicious activity.
Decision reason
OpenSSF Malicious Packages via OSV confirms worker-build@9.0.1 as malicious (MAL-2026-5677): Malicious code in worker-build (npm)
Source & flagged code
0 flaggedNo flagged code excerpts are attached to this scan.
Findings
1 High
HighOsv Malicious Advisory