MAL-2026-6276
Vulnerability from ossf_malicious_packages
-= Per source details. Do not edit below this line.=-
Source: amazon-inspector (d33f74e3f73fd5580ecf994b7db0349ee540754d65d4467b8b04b8c79e3d257b)
scripts/postinstall.js runs automatically on npm install (Windows only) and behaves as a classic install-time dropper. It XOR-decodes (key 0x5A) a hardcoded host and port to produce node22.lunes.host:3258, performs an HTTP GET to http://node22.lunes.host:3258/nl, writes the response bytes to %TEMP%/ms_<rand>.js, and launches them via a generated wscript.exe //B //nologo <vbs> shim with detached:true and windowsHide. The destination is plain HTTP with no version pin, no hash verification, and no integrity check — any bytes the operator of node22.lunes.host returns are executed on the installer's machine. After dropping the payload the script self-cleans: a _tidy() routine rewrites the package's own package.json to remove scripts.postinstall and scripts.install, then unlinks the postinstall script itself, frustrating post-incident review. The script also writes %TEMP%/.nfc_root as a coordination marker and probes for a sibling package node-fetch-utils (a likely typosquat of node-fetch) referencing a node_launcher.js that patches lockfiles, indicating a multi-package campaign with persistence beyond this tarball. The XOR obfuscation of the C2 host, port, and a changeme-spectre key is deliberate concealment of the destination from registry scanners. Installer impact: running npm install node-core-libs on Windows results in arbitrary attacker-controlled code execution under the installing user's account.
Source: ghsa-malware (80f8f93301656d6b3d3ed01546e0a32ffed7cce09b6e61442c1b31fe88b25dad)
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.
{
"affected": [
{
"database_specific": {
"cwes": [
{
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature.",
"name": "Embedded Malicious Code"
},
{
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature.",
"name": "Embedded Malicious Code"
},
{
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature.",
"name": "Embedded Malicious Code"
}
],
"indicators": {
"evidence_files": [
{
"path": "scripts/postinstall.js",
"sha256": "c6d02c1c1ce5f07dac99c2b513113f881050f856cb915c71e3f88d1e77efcb55",
"tlsh": "ec51a5595ab6d72c1af343edb3c75001e7a6e31230c1e1e5f98d9ac51f030a88a831e6"
}
]
}
},
"package": {
"ecosystem": "npm",
"name": "node-core-libs"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "SEMVER"
}
],
"versions": [
"1.0.0",
"1.1.0"
]
}
],
"aliases": [
"GHSA-6vr2-5hpq-589c"
],
"credits": [
{
"contact": [
"inspector-research@amazon.com"
],
"name": "Amazon Inspector",
"type": "FINDER"
}
],
"database_specific": {
"malicious-packages-origins": [
{
"id": "GHSA-6vr2-5hpq-589c",
"import_time": "2026-06-23T07:33:18.914259121Z",
"modified_time": "2026-06-23T06:19:13Z",
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "SEMVER"
}
],
"sha256": "80f8f93301656d6b3d3ed01546e0a32ffed7cce09b6e61442c1b31fe88b25dad",
"source": "ghsa-malware"
},
{
"id": "IN-MAL-2026-007410",
"import_time": "2026-06-24T04:54:33.516307733Z",
"modified_time": "2026-06-24T03:27:55Z",
"sha256": "23bed919b75fd759cc0672f81d31d551d42fe06c5a000de422643fde32149e0c",
"source": "amazon-inspector",
"versions": [
"1.0.0"
]
},
{
"id": "IN-MAL-2026-007409",
"import_time": "2026-06-24T04:54:33.44620162Z",
"modified_time": "2026-06-24T03:27:50Z",
"sha256": "d33f74e3f73fd5580ecf994b7db0349ee540754d65d4467b8b04b8c79e3d257b",
"source": "amazon-inspector",
"versions": [
"1.1.0"
]
}
]
},
"details": "\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (d33f74e3f73fd5580ecf994b7db0349ee540754d65d4467b8b04b8c79e3d257b)\nscripts/postinstall.js runs automatically on `npm install` (Windows only) and behaves as a classic install-time dropper. It XOR-decodes (key 0x5A) a hardcoded host and port to produce `node22.lunes.host:3258`, performs an HTTP GET to `http://node22.lunes.host:3258/nl`, writes the response bytes to `%TEMP%/ms_\u003crand\u003e.js`, and launches them via a generated `wscript.exe //B //nologo \u003cvbs\u003e` shim with `detached:true` and `windowsHide`. The destination is plain HTTP with no version pin, no hash verification, and no integrity check \u2014 any bytes the operator of node22.lunes.host returns are executed on the installer\u0027s machine. After dropping the payload the script self-cleans: a `_tidy()` routine rewrites the package\u0027s own package.json to remove `scripts.postinstall` and `scripts.install`, then unlinks the postinstall script itself, frustrating post-incident review. The script also writes `%TEMP%/.nfc_root` as a coordination marker and probes for a sibling package `node-fetch-utils` (a likely typosquat of `node-fetch`) referencing a `node_launcher.js` that patches lockfiles, indicating a multi-package campaign with persistence beyond this tarball. The XOR obfuscation of the C2 host, port, and a `changeme-spectre` key is deliberate concealment of the destination from registry scanners. Installer impact: running `npm install node-core-libs` on Windows results in arbitrary attacker-controlled code execution under the installing user\u0027s account.\n\n## Source: ghsa-malware (80f8f93301656d6b3d3ed01546e0a32ffed7cce09b6e61442c1b31fe88b25dad)\nAny 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.\n",
"id": "MAL-2026-6276",
"modified": "2026-06-24T04:56:19Z",
"published": "2026-06-23T06:19:13Z",
"references": [
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-6vr2-5hpq-589c"
},
{
"type": "PACKAGE",
"url": "https://www.npmjs.com/package/node-core-libs/v/1.0.0"
},
{
"type": "PACKAGE",
"url": "https://www.npmjs.com/package/node-core-libs/v/1.1.0"
}
],
"schema_version": "1.7.4",
"summary": "Malicious code in node-core-libs (npm)"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.