-= Per source details. Do not edit below this line.=-
On require of the package's main entry, polyfill.js executes init() which reconstructs destination hostnames via array-join string splits (e.g. ["oob-worke","r.cf100-416.worker","s.","dev"].join("")), selects a platform-specific endpoint, downloads an opaque binary via https.get from one of several Cloudflare Workers subdomains (oob-worker.cf100-416.workers.dev, cf101-adf, cf102-baf, cf103-070.workers.dev), writes the payload to /tmp or %TEMP% under a disguised name (.cache on Unix, dotnet_diag_.exe on Windows), chmods it 0755, and spawns it detached via spawn("/bin/sh",["-c",fp+" &"],{detached:true,stdio:"ignore"}).unref() or spawn("cmd",...). If HTTPS retrieval fails, a fallback path resolves TXT records at c. and iteratively at N. under *.dl.wel1.ru (sdk/ext/pkg/net subdomains), base64-concatenates the chunks, and treats the result as the executable payload. Host reconstruction, disguised file names, staging in temp directories, detached execution, and a DNS TXT covert-channel fallback together constitute a fully productionized install-time dropper delivering arbitrary attacker code to any machine that installs or requires this package.
{
"malicious-packages-origins": [
{
"id": "IN-MAL-2026-015008",
"import_time": "2026-08-05T14:19:52.115976044Z",
"modified_time": "2026-08-05T13:42:39Z",
"sha256": "638c4246220ea7f9a595c145c76940e7e060920ef251ab2c67ca814b9ab93378",
"source": "amazon-inspector",
"versions": [
"35.7.9"
]
}
]
}[
{
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature.",
"name": "Embedded Malicious Code"
}
]
{
"evidence_files": [
{
"path": "_polyfill.js",
"sha256": "0a4c3a06201873689403c0c12b5cfee92242b73e209f042d70eebfd5f2d2313e",
"tlsh": "e7a1a76612a670084bb09be4c71b4816f65af6633781c1c4fb5c65945f731248372efc"
}
],
"package_integrity": [
{
"filename": "devplatform-spa-plugin-module-35.7.9.tgz",
"hashes": {
"sha1": "beeb2c0c251b536d8145e2d0373c8e0656c02318",
"sha512_sri": "sha512-L4awH0vivpvrs8JBFIhHJiz50nblsi67n+0UZUIlOnoQ65RmB8wshocLEZxu61B41bSqxYfktlxUQqX8Ti9g+g=="
}
}
]
}
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/devplatform-spa-plugin-module/MAL-2026-12771.json"