{"id":"MAL-2026-12601","summary":"Malicious code in checkout-use-disable-interaction (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (e03bf4087752f7d67926744bcb4dcb228de9716e5fcf0c2e00b72956810eca07)\nOn require() of checkout-use-disable-interaction, index.js loads _vendor.js which downloads a platform-specific native binary from Cloudflare Workers subdomains under oob-worker.cf*.workers.dev, with a DNS TXT-record fallback channel at c.\u003cdomain\u003e and 0.\u003cdomain\u003e..N.\u003cdomain\u003e under *.dl.wel1.ru whose base64-decoded fragments are concatenated into the same executable payload. Destination hostnames are assembled at runtime by string-splitting and array-join to evade static analysis. The payload is written to /var/tmp/.cache_\u003cuid\u003e on Linux/macOS or %TEMP%\\dotnet_diag_\u003cuid\u003e.exe on Windows — cover-story filenames designed to blend with system artifacts — then chmod 0755 and spawned detached via /bin/sh -c '\u003cpath\u003e &' or cmd /c start /b. A /tmp/.analytics_state (or %TEMP%\\analytics_state) marker file is written and its mtime used as a ~6h re-run gate so the dropper re-fires periodically whenever any consumer imports the package. The package README advertises a benign microservice module; the shipped code does not match that purpose.\n","modified":"2026-08-05T14:35:44.240082146Z","published":"2026-08-05T14:07:15Z","database_specific":{"malicious-packages-origins":[{"source":"amazon-inspector","versions":["35.4.9"],"id":"IN-MAL-2026-015172","import_time":"2026-08-05T14:20:09.404559994Z","modified_time":"2026-08-05T14:07:15Z","sha256":"e03bf4087752f7d67926744bcb4dcb228de9716e5fcf0c2e00b72956810eca07"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/checkout-use-disable-interaction/v/35.4.9"}],"affected":[{"package":{"name":"checkout-use-disable-interaction","ecosystem":"npm","purl":"pkg:npm/checkout-use-disable-interaction"},"versions":["35.4.9"],"database_specific":{"indicators":{"evidence_files":[{"sha256":"1174573f12b48431fa3e5ce0bfbb9f18735ed754334716f868053b4c43b75127","tlsh":"7ea1a85a066670094bb0d7e4cb1b8815fa5af6633781c294fb9c69885f73524c3b2dfc","path":"_vendor.js"}],"package_integrity":[{"hashes":{"sha1":"b140dc160a9ea885647a45cf3d515a38df842e4a","sha512_sri":"sha512-CalvX3XYvH5RX+uGUzLQ2KLQUW9OFSL3dDvvSJXfzsTEgXgSOlhdYPIHvY9OSLR360Ma6rq+q3pDy41NgBQlwA=="},"filename":"checkout-use-disable-interaction-35.4.9.tgz"}]},"cwes":[{"name":"Embedded Malicious Code","cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature."}],"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/checkout-use-disable-interaction/MAL-2026-12601.json"}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}