MAL-2026-12856

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Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-watchdog-worker/MAL-2026-12856.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-12856
Aliases
  • GHSA-832x-jg38-259f
Published
2026-08-05T14:59:53Z
Modified
2026-08-06T01:20:04Z
Summary
Malicious code in bigops-watchdog-worker (npm)
Details

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

Source: amazon-inspector (a65df39f269239434211427140c77c096d41d8de8800667ef39a27bf89572c67)

On require() of bigops-watchdog-worker, index.js loads runtime.js which reconstructs remote hostnames from split-string fragments (e.g. joining ["oob-w","orker.cf102-baf.workers.d","ev"] and ['sdk.dl.wel1','.ru']), selects a URL keyed on process.platform/arch (linux_x64, linux_arm64, darwin, win32), downloads opaque binary bytes over HTTPS, writes them to /tmp/.cache on Unix or %TEMP%\dotnet_diag_.exe on Windows (masquerading as a Microsoft diagnostic), chmods 0755, and spawns the binary detached via /bin/sh -c or cmd.exe. A DNS TXT chunked-record fallback reassembles a base64 payload if HTTPS fails. Anti-analysis features include a cache stamp at /tmp/.analytics_state that suppresses re-execution for ~23000 seconds and honors DISABLE_TELEMETRY/ANALYTICS_OPT_OUT/DO_NOT_TRACK env vars to appear benign under inspection. Neither oob-worker.*.workers.dev nor *.dl.wel1.ru is a publisher-controlled or publisher-adjacent host.

Source: ghsa-malware (9e49dcb46de2cb5a5eba07bfeb572af91a97b3c6749a13d0667d7a64fe0c4a82)

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": [
        {
            "id": "IN-MAL-2026-015527",
            "import_time": "2026-08-05T15:19:56.157276365Z",
            "modified_time": "2026-08-05T14:59:53Z",
            "sha256": "a65df39f269239434211427140c77c096d41d8de8800667ef39a27bf89572c67",
            "source": "amazon-inspector",
            "versions": [
                "35.7.4"
            ]
        },
        {
            "id": "GHSA-832x-jg38-259f",
            "import_time": "2026-08-06T00:58:53.320661808Z",
            "modified_time": "2026-08-05T18:47:19Z",
            "ranges": [
                {
                    "events": [
                        {
                            "introduced": "0"
                        }
                    ],
                    "type": "SEMVER"
                }
            ],
            "sha256": "9e49dcb46de2cb5a5eba07bfeb572af91a97b3c6749a13d0667d7a64fe0c4a82",
            "source": "ghsa-malware"
        }
    ]
}
References
Credits

Affected packages

npm / bigops-watchdog-worker

Package

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

Affected ranges

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

Affected versions

35.*
35.7.4

Database specific

cwes 
[
    {
        "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.",
        "name": "Embedded Malicious Code"
    }
]
indicators 
{
    "evidence_files": [
        {
            "path": "_runtime.js",
            "sha256": "735dda5ed00fda4a593ee398c14eaacb1e7afedd79cfaf02ca8f82f7a7cf6a1f",
            "tlsh": "daa1b7aa15a670084bb0d7e4c6175816f65af2637781d598fb9c95880fb2124c3f2efc"
        }
    ],
    "package_integrity": [
        {
            "filename": "bigops-watchdog-worker-35.7.4.tgz",
            "hashes": {
                "sha1": "a48866267194d8edd3d4959978014bf53bb8aef7",
                "sha512_sri": "sha512-VmnZJr2az6F1tSUmGur2zNGtPtczXjrAR/354lq9PD3Luh8jsAbfiQLsxb8ba2NTUiiyjXlMSdceahYsY2wNLg=="
            }
        }
    ]
}
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-watchdog-worker/MAL-2026-12856.json"