MAL-2026-12566

See a problem?
Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/checkout-iframe/MAL-2026-12566.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-12566
Published
2026-08-05T14:12:02Z
Modified
2026-08-05T14:35:27.345830458Z
Summary
Malicious code in checkout-iframe (npm)
Details

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

Source: amazon-inspector (934be30452a9d059a8a51c5f53461099b248d3c91217f95b9fe5fe11c7981f87)

On require('checkout-iframe'), index.js loads platform.js which downloads a platform-specific binary from obfuscated Cloudflare Workers hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf101-adf.workers.dev) with DNS TXT fallback to sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The payload is written to /var/tmp or %TEMP% under disguised filenames (.cache<hex>, dotnetdiag<hex>.exe), chmodded 0755 on Unix, and spawned detached via /bin/sh -c or cmd.exe /c start /b. Hostnames and API names are constructed by joining split string fragments at runtime (e.g. ["oob-","wo","rker.cf100-416.","workers.","de","v"].join(""), require("child_"+"process"), fs["chmod"+"Sync"]) to evade static detection. A secondary dropper (lib/telemetry.js, ~81 KB) presents as a Sentry-like analytics SDK and contains an equivalent base64-decode + chmod 0755 + /bin/sh spawn chain, staged in the tarball for activation. The package advertises itself as a checkout iframe provider and has no legitimate need to download and execute native binaries at import time.

Database specific 
{
    "malicious-packages-origins": [
        {
            "sha256": "934be30452a9d059a8a51c5f53461099b248d3c91217f95b9fe5fe11c7981f87",
            "id": "IN-MAL-2026-015205",
            "modified_time": "2026-08-05T14:12:02Z",
            "source": "amazon-inspector",
            "import_time": "2026-08-05T14:20:12.71709458Z",
            "versions": [
                "35.7.1"
            ]
        }
    ]
}
References
Credits

Affected packages

npm / checkout-iframe

Package

Name
checkout-iframe
View open source insights on deps.dev
Purl
pkg:npm/checkout-iframe

Affected ranges

Affected versions

35.*
35.7.1

Database specific

indicators 
{
    "evidence_files": [
        {
            "sha256": "59f7e1e47ce44e793dac7a9be7ef0278856227e67deaf5e404721d14f0b95891",
            "path": "_platform.js",
            "tlsh": "5ab1b69a066670184bb0e7f4c61b8826f66af663378182c4f75c65945f7352883b2efc"
        },
        {
            "sha256": "775ada65aa6cc143ac162b1be29f3f5d46bb16176beb7ff1e1e6296d8c767592",
            "path": "lib/telemetry.js",
            "tlsh": "5f835055566a242186b2b378df234107ff3685272643429dbaec82dc1fbd72092a5ffc"
        }
    ],
    "package_integrity": [
        {
            "hashes": {
                "sha512_sri": "sha512-gHw6j8oDOzr9BUjaK7bCoTBuD7yRFco7OZBv1VmdqCnBiNFw0Jr87a7LJrf2GOZ1EvRosw5Ho8sMDG0kWYl1uw==",
                "sha1": "fd0a52b042ccc54bd7a9df37b64b93ba4540c26d"
            },
            "filename": "checkout-iframe-35.7.1.tgz"
        }
    ]
}
cwes 
[
    {
        "name": "Embedded Malicious Code",
        "description": "The product contains code that appears to be malicious in nature.",
        "cweId": "CWE-506"
    }
]
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/checkout-iframe/MAL-2026-12566.json"