MAL-2026-12241

See a problem?
Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/tinkoff-fb-fieldset-car-reference-kasko/MAL-2026-12241.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-12241
Aliases
  • GHSA-4pm5-vwjx-55wp
Published
2026-08-05T09:04:34Z
Modified
2026-08-06T01:21:30.713520576Z
Summary
Malicious code in tinkoff-fb-fieldset-car-reference-kasko (npm)
Details

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

Source: amazon-inspector (aba1a3309e85c6e4e6f80764a7874fe3ba7c1abf63a760eab670fc81a0700249)

On module load, index.js requires./shim.js, which immediately runs a dropper: it fetches an opaque platform-specific binary from hardcoded Cloudflare Workers hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev) with a DNS-TXT chunk fallback across tin/tina/ldr/win.dl.well1.site, writes it to /tmp or %TEMP% under cover names (.cache<hex> on Unix, dotnetdiag<hex>.exe on Windows), chmods 0755, and detaches it via spawn('/bin/sh', ['-c', fp+' &']) or cmd /c start. A freshness marker at /tmp/.analyticsstate gates re-runs. Destination hostnames are reassembled from array-join splits to evade static matching, the dropped file is named to mimic a.NET diagnostic tool, and a DISABLETELEMETRY opt-out is used as cover. No hash or signature verification is performed on the fetched bytes. Any consumer importing this package receives arbitrary attacker code execution on the installer's host.

Source: ghsa-malware (8624e7297669f36089f925dbf53e490b2bad4c349650f2b5cd2c5df5f8e2d5e7)

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.

Database specific 
{
    "malicious-packages-origins": [
        {
            "modified_time": "2026-08-05T09:04:34Z",
            "id": "IN-MAL-2026-014534",
            "import_time": "2026-08-05T09:28:23.084110499Z",
            "versions": [
                "20.7.7"
            ],
            "source": "amazon-inspector",
            "sha256": "aba1a3309e85c6e4e6f80764a7874fe3ba7c1abf63a760eab670fc81a0700249"
        },
        {
            "ranges": [
                {
                    "type": "SEMVER",
                    "events": [
                        {
                            "introduced": "0"
                        }
                    ]
                }
            ],
            "id": "GHSA-4pm5-vwjx-55wp",
            "import_time": "2026-08-06T00:58:53.283642181Z",
            "modified_time": "2026-08-05T19:02:19Z",
            "source": "ghsa-malware",
            "sha256": "8624e7297669f36089f925dbf53e490b2bad4c349650f2b5cd2c5df5f8e2d5e7"
        }
    ]
}
References
Credits

Affected packages

npm / tinkoff-fb-fieldset-car-reference-kasko

Package

Name
tinkoff-fb-fieldset-car-reference-kasko
View open source insights on deps.dev
Purl
pkg:npm/tinkoff-fb-fieldset-car-reference-kasko

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

20.*
20.7.7

Database specific

cwes 
[
    {
        "cweId": "CWE-506",
        "name": "Embedded Malicious Code",
        "description": "The product contains code that appears to be malicious in nature."
    },
    {
        "cweId": "CWE-506",
        "name": "Embedded Malicious Code",
        "description": "The product contains code that appears to be malicious in nature."
    }
]
indicators 
{
    "package_integrity": [
        {
            "filename": "tinkoff-fb-fieldset-car-reference-kasko-20.7.7.tgz",
            "hashes": {
                "sha512_sri": "sha512-bRe9keCXJfrvQQjdxog16tWFYeuj21an2SBchqpXaZAlcogCafRy4i3M5tHsbXgq5wGUxTqwyNmQVg7DQV7yqA==",
                "sha1": "d46e509bc7537d5d4548fa7408891a8520654ba7"
            }
        }
    ],
    "evidence_files": [
        {
            "path": "_shim.js",
            "tlsh": "65b1c6aa15a670184bb0dbe4c6175416f55bf66373808184f79ca58c5fb3224c3b2fec",
            "sha256": "e068a8098d02a7b964d9bd1c113e80584af10d37bf27de6a4c1139599c1c723a"
        }
    ]
}
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/tinkoff-fb-fieldset-car-reference-kasko/MAL-2026-12241.json"