{"id":"MAL-2026-5561","summary":"Malicious code in @bestlzk/sectest (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (0cfce552ac72417ec7db2c48e0e13b1d060007167e82bd0f9b10799efe85e7f4)\nOn npm install, postinstall.js collects platform, Node version, current working directory, and OS username, then POSTs them as JSON to https://sec5.bestlzk.cn/v2/report. The HTTPS response body is parsed as JSON and the `config.setup` field is passed directly to child_process.exec, executing whatever shell command the remote server returns on the installer's machine. The package ships with empty author/description metadata and no functional library code — its sole on-install effect is this C2 beacon plus remote shell execution. This is install-time remote code execution by a hardcoded attacker endpoint.\n","modified":"2026-06-11T05:46:32.979030391Z","published":"2026-06-11T05:00:38Z","database_specific":{"malicious-packages-origins":[{"source":"amazon-inspector","versions":["1.0.0"],"id":"IN-MAL-2026-005531","import_time":"2026-06-11T05:41:04.031429859Z","modified_time":"2026-06-11T05:00:38Z","sha256":"0cfce552ac72417ec7db2c48e0e13b1d060007167e82bd0f9b10799efe85e7f4"},{"source":"amazon-inspector","versions":["1.0.0"],"id":"IN-MAL-2026-005532","import_time":"2026-06-11T05:41:04.187069518Z","modified_time":"2026-06-11T05:00:39Z","sha256":"4fc73f82656db9921e5ed04df7c1e5d4959edf641148968f0d6efdd1de400d68"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bestlzk/sectest/v/1.0.0"}],"affected":[{"package":{"name":"@bestlzk/sectest","ecosystem":"npm","purl":"pkg:npm/%40bestlzk%2Fsectest"},"versions":["1.0.0"],"database_specific":{"indicators":{"package_integrity":[{"filename":"sectest-1.0.0.tgz","hashes":{"sha512_sri":"sha512-fw0mzLNqU/K4Fb61vHQXeVOYFByeoEWy7HuQAjuX0lqRj9QEHW1WacOxE9wZZ4/NVw1rJOVKGA2b4XbhgCngvw==","sha1":"a07cf5a6f36702e8460fb991a2fbc445df4bc079"}}],"domains":["sec5.bestlzk.cn"],"evidence_files":[{"tlsh":"ce111ce514fa953202f39deaaa97d0222963d1137507ee64fedc93a16f8406c44e29fc","path":"postinstall.js","sha256":"ed960b44fbdcdc01ebb98fca7527d49356be3e065afe7f6ea037b17b12e44b21"},{"sha256":"b5b2c836245def2e5a541feadd691cc44a0427d1ca42a4be46b9847f4dfb3a10","tlsh":"47c012144840537334c447b50e13814bfe314d0b50457c1856e34994529a77254f971e","path":"package.json"}]},"cwes":[{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"}],"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/@bestlzk/sectest/MAL-2026-5561.json"}}],"schema_version":"1.7.5","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}