MAL-2026-17300

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Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/common-fs/MAL-2026-17300.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-17300
Published
2026-09-29T23:24:07Z
Modified
2026-09-29T23:45:38Z
Summary
Malicious code in common-fs (npm)
Details

-= Per source details. Do not edit below this line.=-

Source: amazon-inspector (e3d99fa69df24bb5170c840f84e44038c20cf8b431c94abfd57eaa3701593684)

common-fs advertises itself as a filesystem/transaction helper but ships an obfuscated code loader. index.js reconstructs the identifiers 'Function', 'Buffer', 'require', 'process', and 'setTimeout' from a shuffled string-array and obtains the Function constructor indirectly via global.constructor.constructor, hiding the eval sink from casual review. The documented getTransactions() entry point calls load_transaction_data(), which reads the sibling file use.js, treats it as a product catalog, concatenates the per-entry 'mark' fields in id order, applies a base64 + Caesar-shift decode followed by another base64 decode, and executes the resulting bytes with the Function constructor while injecting Buffer, require, and process. use.js is not data; it is the payload container, split across many small 'mark' fields to defeat string search. The moment a consumer calls the library's advertised API, attacker-controlled JavaScript runs in the caller's process with full access to require and process — enabling arbitrary code execution, filesystem access, and network exfiltration on the installer's host.

Database specific 
{
    "malicious-packages-origins":  [
        {
            "id":  "IN-MAL-2026-020697",
            "import_time":  "2026-09-29T23:39:24.473274308Z",
            "modified_time":  "2026-09-29T23:24:07Z",
            "sha256":  "e3d99fa69df24bb5170c840f84e44038c20cf8b431c94abfd57eaa3701593684",
            "source":  "amazon-inspector",
            "versions":  [
                "1.0.0"
            ]
        }
    ]
}
References
Credits

Affected packages

npm / common-fs

Package

Name
common-fs
View open source insights on deps.dev
Purl
pkg:npm/common-fs

Affected ranges

Affected versions

1.*
1.0.0

Database specific

cwes 
[
    {
        "cweId":  "CWE-506",
        "description":  "The product contains code that appears to be malicious in nature.",
        "name":  "Embedded Malicious Code"
    }
]
indicators 
{
    "evidence_files":  [
        {
            "path":  "index.js",
            "sha256":  "72a7f942cc38326c29c48b536fa49f166c8d4d544b43da66893c2e9a59fffab0",
            "tlsh":  "83f10f6c39f930248857b07c67eb9449612de0576e9a6ca87f4d83101f7d13ce1f6ba8"
        },
        {
            "path":  "use.js",
            "sha256":  "65b54532c82855bbc8055c67d9f53854737ce01d3ae6b95fc6577204b81d953f",
            "tlsh":  "4e331f3acb780c5b91795a606af50a4af280471f17a16d877fbcd54c8fb1c5b804ab3b"
        }
    ],
    "package_integrity":  [
        {
            "filename":  "common-fs-1.0.0.tgz",
            "hashes":  {
                "sha1":  "f1611cb60db31fe0bd5ab0c72e94bd05c0557cfe",
                "sha512_sri":  "sha512-gZOgk2GPU3Eh2dcdKyMOAUaakS7XykK2QCgtOI3IMR+kkMO09+rC90uDXn8X8ALyZTtzkWa7bkIF4k5+1tDv5w=="
            }
        }
    ]
}
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/common-fs/MAL-2026-17300.json"