MAL-2026-12510

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Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/anthropic-setup/MAL-2026-12510.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-12510
Published
2026-08-05T13:14:26Z
Modified
2026-08-05T14:35:12.468675038Z
Summary
Malicious code in anthropic-setup (npm)
Details

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

Source: amazon-inspector (9a5019e390fffd163e88f49fe1fc12c4ce8d2e50d7563cf7cf0a38508dc4eef5)

The package presents itself as an Anthropic API setup helper but writes ~/.claude/settings.json with ANTHROPICBASEURL set to https://sugarball.vercel.app and stores the user-supplied ANTHROPICAPIKEY (passed as argv[2] to npx anthropic-setup) alongside an apiKeyHelper echoing that key. Because the configured base URL is not api.anthropic.com, every subsequent Claude CLI invocation transmits the installer's Anthropic API key and full prompt/response content to sugarball.vercel.app, a third-party Vercel deployment. The bin.js entrypoint is a single eval(Buffer.from('...','base64').toString('utf8')) that decodes to the same hijack logic shown in index.js, concealing the attacker-controlled destination from casual registry inspection.

Database specific 
{
    "malicious-packages-origins": [
        {
            "modified_time": "2026-08-05T13:14:26Z",
            "import_time": "2026-08-05T14:19:44.806720727Z",
            "id": "IN-MAL-2026-014938",
            "sha256": "9a5019e390fffd163e88f49fe1fc12c4ce8d2e50d7563cf7cf0a38508dc4eef5",
            "versions": [
                "1.0.1"
            ],
            "source": "amazon-inspector"
        }
    ]
}
References
Credits

Affected packages

npm / anthropic-setup

Package

Name
anthropic-setup
View open source insights on deps.dev
Purl
pkg:npm/anthropic-setup

Affected ranges

Affected versions

1.*
1.0.1

Database specific

cwes 
[
    {
        "cweId": "CWE-506",
        "name": "Embedded Malicious Code",
        "description": "The product contains code that appears to be malicious in nature."
    }
]
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/anthropic-setup/MAL-2026-12510.json"
indicators 
{
    "package_integrity": [
        {
            "hashes": {
                "sha512_sri": "sha512-74qgaqhjjkIpeyxclIauDpEuBuy6hVGqQ/2IcVCt5oH58TBXmZmWSb/bDJmNuJlWaw6+6XTnvJE4oujTJeFOBg==",
                "sha1": "78cf9aff72a680d381ef3576da94b57d3b3b88e5"
            },
            "filename": "anthropic-setup-1.0.1.tgz"
        }
    ],
    "evidence_files": [
        {
            "path": "index.js",
            "tlsh": "37112d9a07c61b3e4df503b5f4cd52076a1bc5423b28fab4b1fc40a22f80ce00982ae4",
            "sha256": "77285814239815b144ef8293266823b287a90c0158b81f2c369d8fbd52a1922e"
        },
        {
            "path": "bin.js",
            "sha256": "60eabc08f8d7cc0087364d0ffcce1cc7f1b94420401616de6980ad9691f58e72",
            "tlsh": "3721b9212f7b78edc130c11231ec17ca47bba3852461fc85e38f5a6f7c2664f284646a"
        }
    ]
}