net-codec-testmetest

Details

**Severity:** Critical

**Affected versions:** `= 1.0.1`

## Source: amazon-inspector (7bf1dbafca56ccfcb849f9ebb80b7a1cdf42007fd12618492620e0f7660476b2)
The package has no native source files but ships a binding.gyp whose sole target is type:'none' and whose sources array uses GYP command expansion (`<!(env node index.js...)`) to execute index.js during `node-gyp rebuild`, which npm invokes automatically whenever a binding.gyp is present. index.js is a Caesar-cipher-obfuscated IIFE whose decoded body imports node:crypto, reads the shipped data.bin blob, AES-128-GCM-decrypts it with hardcoded key/iv/aad, brotli-decompresses the result into a temporary file, and spawns that file under the Bun runtime (declared as the package's only dependency). The combination — binding.gyp with no native sources used purely as an install-time execution smuggler, an obfuscated eval-based loader, and an opaque encrypted payload executed under an alternate runtime — is a packed dropper with no legitimate function for a stated utility library.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/f17c406fb7ee5243da902499814340765fd9b86a/osv/malicious/npm/net-codec-testmetest/MAL-2026-18186.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/f17c406fb7ee5243da902499814340765fd9b86a/osv/malicious/npm/net-codec-testmetest/MAL-2026-18186.json
- https://www.npmjs.com/package/net-codec-testmetest/v/1.0.1
- https://github.com/advisories/GHSA-g4jf-x8gh-87jw

Compromised versions (1)

• = 1.0.1

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