MAL-2026-12857

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Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-watermark/MAL-2026-12857.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-12857
Aliases
  • GHSA-pvr5-5pcp-mh66
Published
2026-08-05T14:59:08Z
Modified
2026-08-06T01:20:04.632130380Z
Summary
Malicious code in bigops-watermark (npm)
Details

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

Source: amazon-inspector (e1eba25818a15259edb9be7c7629e7319599a0ba7ac7a665f976c78ffb1e56f3)

On require() of the package, index.js unconditionally loads support.js, whose init() runs at module load. It selects a platform-specific endpoint, fetches an opaque binary from string-obfuscated *.workers.dev hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev) with DNS-TXT base64 fallbacks resolving to sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru, writes the payload to /tmp or %TEMP% under a disguised name (.cache<hex> or dotnetdiag<hex>.exe), chmods it 0755, and spawns it detached via /bin/sh -c or cmd. No hash or signature verification is performed and there is no user opt-in. Hostnames and sensitive APIs are assembled from split string fragments joined at runtime (e.g. require("child_"+"process"), fs["chmod"+"Sync"]) to evade static analysis, and environment-variable names such as DISABLETELEMETRY / ANALYTICSOPT_OUT are used as cover. A duplicate dropper implementation is also shipped in lib/telemetry.js (an 80KB file styled as an analytics SDK) containing the same fetch/chmod-755/spawn primitives and base64 chunk assembly; it is not currently reachable from the main import path but mirrors the active payload.

Source: ghsa-malware (e7aaf8160096633a054d39673abfde65692456873183ffda84f9c680361ae4a1)

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": [
        {
            "source": "amazon-inspector",
            "modified_time": "2026-08-05T14:59:08Z",
            "sha256": "e1eba25818a15259edb9be7c7629e7319599a0ba7ac7a665f976c78ffb1e56f3",
            "id": "IN-MAL-2026-015522",
            "versions": [
                "35.9.5"
            ],
            "import_time": "2026-08-05T15:19:55.948795207Z"
        },
        {
            "import_time": "2026-08-06T00:58:53.430432219Z",
            "sha256": "e7aaf8160096633a054d39673abfde65692456873183ffda84f9c680361ae4a1",
            "ranges": [
                {
                    "type": "SEMVER",
                    "events": [
                        {
                            "introduced": "0"
                        }
                    ]
                }
            ],
            "id": "GHSA-pvr5-5pcp-mh66",
            "modified_time": "2026-08-05T18:48:10Z",
            "source": "ghsa-malware"
        }
    ]
}
References
Credits

Affected packages

npm / bigops-watermark

Package

Name
bigops-watermark
View open source insights on deps.dev
Purl
pkg:npm/bigops-watermark

Affected ranges

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

Affected versions

35.*
35.9.5

Database specific

cwes 
[
    {
        "name": "Embedded Malicious Code",
        "cweId": "CWE-506",
        "description": "The product contains code that appears to be malicious in nature."
    },
    {
        "name": "Embedded Malicious Code",
        "cweId": "CWE-506",
        "description": "The product contains code that appears to be malicious in nature."
    }
]
indicators 
{
    "package_integrity": [
        {
            "hashes": {
                "sha512_sri": "sha512-+aik0FyqmmMH8RAomrs6AV60S+/vPYjXkf5iZ0edhtj1rZul58E/wtWwGcGSL9lU6DhDF2uo7v1z8ZhznGLwBQ==",
                "sha1": "59e8cf9074a72788229645a29bb13d1a56c3cd9a"
            },
            "filename": "bigops-watermark-35.9.5.tgz"
        }
    ],
    "evidence_files": [
        {
            "path": "_support.js",
            "sha256": "1bb9bd047294973206587b893f10ebcec88b2e1e756797fb950dd0b91f5d794d",
            "tlsh": "46a1966a166770084bb09be1c7175416f61ae66377c0c684fb9ca5881ff212483b2efc"
        },
        {
            "path": "lib/telemetry.js",
            "sha256": "15bea310554f9458a62959ec21c2c905525bfd9d80046dcd1598af13bef211f2",
            "tlsh": "f5835055566a242186b2b368df234107ff3685272643429dbafc82dc1fbd72092a5ffc"
        }
    ]
}
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-watermark/MAL-2026-12857.json"