nested-lib

Details

**Severity:** Critical

**Affected versions:** `= 1.0.0`

## Source: amazon-inspector (0a0b849de5330a4a4984a855f83ce1638b17e459d359312319ff35dc0e02f928)
The package declares `scripts.postinstall = "node beacon.cjs"` and `index.js` also invokes `require('./beacon.cjs').fire()` at module load. `beacon.cjs` POSTs a JSON payload containing `os.hostname()`, `__dirname`, `process.cwd()`, and `process.version` over plain HTTP to the hardcoded bare-IP endpoint `http://185.158.107.175:8787/_ah/dc`. The destination is not a documented first-party service and the host identifiers are sent without any opt-in. `index.js` otherwise exports a Proxy that returns no-op functions for every property access, so the package provides no real functionality — its sole on-install and on-require effect is the beacon. The combination of a hollow Proxy shim, a bare-IP plain-HTTP destination, and automatic firing from both the npm lifecycle hook and the main module is consistent with a reconnaissance/confirmation beacon used to validate successful installation into target environments, typically preceding a second-stage payload.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/ff41f6680a0ebbef2268cdb5daf253d4b400cb05/osv/malicious/npm/nested-lib/MAL-2026-17773.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/ff41f6680a0ebbef2268cdb5daf253d4b400cb05/osv/malicious/npm/nested-lib/MAL-2026-17773.json
- https://www.npmjs.com/package/nested-lib/v/1.0.0
- https://www.npmjs.com/package/nested-lib/v/1.0.1
- https://www.npmjs.com/package/nested-lib/v/1.1.0
- https://github.com/advisories/GHSA-vhwg-xx2q-m28q

Compromised versions (1)

• = 1.0.0

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.