Malicious code in fs-commons (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (f7e82e98343807c39ea786017de4d2a7455815424155ca2a856333d895c8a48b) The package presents itself as a filesystem/data-helper library, but its exported getTransactions()/load_transaction_data() functions are a two-file dynamic-code loader. index.js hides the identifiers 'Function', 'require', 'process', 'Buffer', and 'setTimeout' behind a split-string array and obtains the Function constructor indirectly via globalThis.constructor.constructor, defeating static review. At call time it reads the sibling file models.js, which is disguised as an array of product-record objects but whose `mark` fields are base64 ciphertext. loadConfig()/processData() sort the records by id, concatenate every `mark`, apply a per-count Caesar shift, base64-decode the result, and pass the resulting source to the Function constructor with Buffer, require, and process injected, then invoke it. Any consumer that requires fs-commons and calls getTransactions() executes attacker-supplied code with full Node privileges on the host process. The obfuscation, the indirect Function-constructor acquisition, and the disguising of the payload as product metadata in a sibling file have no legitimate purpose for a data-helper library and are the fingerprint of a supply-chain remote-code-execution package.
MAL-2026-17301
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:MAL-2026-17301
fs-commons
Source reference: /affected/0/package/name
- Affected versions
- 1.0.1
Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"package": {
"name": "fs-commons",
"purl": "pkg:npm/fs-commons",
"ecosystem": "npm"
},
"versions": [
"1.0.1"
],
"database_specific": {
"cwes": [
{
"name": "Embedded Malicious Code",
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature."
}
],
"source": "https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/fs-commons/MAL-2026-17301.json",
"indicators": {
"evidence_files": [
{
"path": "index.js",
"tlsh": "a6f10f6839f930248457b07c67eb9449612de0576e9a6ca87f4d83101f7d13ce1f6ba8",
"sha256": "53a5d6dfb922ca08b58e7c5f5975d885009c0b5a89c0c6805d14832962c21fae"
},
{
"path": "models.js",
"tlsh": "4e331f3acb780c5b91795a606af50a4af280471f17a16d877fbcd54c8fb1c5b804ab3b",
"sha256": "65b54532c82855bbc8055c67d9f53854737ce01d3ae6b95fc6577204b81d953f"
}
],
"package_integrity": [
{
"hashes": {
"sha1": "e50c4a623a29ce361d41d3c91e60ca49bbe9429a",
"sha512_sri": "sha512-hGqVRB9UCGkZy94B9xU1HFy9BUqXGuSbLyRPQZb9GJYINs48j2o/qE3NOHG7g6eMlgpPTcgDc8fA69dWgFDHKQ=="
},
"filename": "fs-commons-1.0.1.tgz"
}
]
}
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #33258 · Revision 1
- Added to Heist Feed
- Publisher date