{"id":"MAL-2026-17808","summary":"Malicious code in @s4yhiitestpoc/r2-https-b (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (e89449bafb4f816bd8605f45cedf0fec8ec0cff9088007a7a38aaea0a9db91ec)\nOn npm install, postinstall.js automatically collects installer-side identifying data — hostname, username, home directory, non-internal network interface addresses, DNS servers, current working directory, install directory, and the value of npm_config_registry (which discloses the installer's internal/private npm registry URL) — and POSTs it as JSON over HTTPS to the hardcoded author endpoint collector.oob.s4yhii.com at path /_npm-poc/beacon. In parallel, the script performs a DNS lookup against a unique per-run subdomain under oob.s4yhii.com (dns.lookup of \u003clabel\u003e.db03o8lag74hsugsg2j091t8mfcf437h3.oob.s4yhii.com), providing an out-of-band DNS confirmation channel that works even when outbound HTTPS is blocked. The dual-channel beacon, the capture of internal registry configuration, and the fully automated install-time trigger match the fingerprint of a dependency-confusion probe. The package's self-description as a proof-of-concept does not change the behavior: installer-side host and internal-infrastructure data leaves the host to an attacker-controlled destination without opt-in.\n","modified":"2026-10-12T05:45:04.513820345Z","published":"2026-10-12T05:27:26Z","database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-021460","import_time":"2026-10-12T05:29:25.256040939Z","modified_time":"2026-10-12T05:27:26Z","sha256":"e89449bafb4f816bd8605f45cedf0fec8ec0cff9088007a7a38aaea0a9db91ec","source":"amazon-inspector","versions":["1.0.0"]}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/@s4yhiitestpoc/r2-https-b/v/1.0.0"}],"affected":[{"package":{"name":"@s4yhiitestpoc/r2-https-b","ecosystem":"npm","purl":"pkg:npm/%40s4yhiitestpoc/r2-https-b"},"versions":["1.0.0"],"database_specific":{"cwes":[{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"}],"indicators":{"evidence_files":[{"sha256":"4e1c182ebf45e34a28a3e7b757eb8442d3b307372dbbc0d2b50898c03fb738d6","tlsh":"1871a56619b4063227e52ee169862094972ac767791cbae0721e13485fce1be40f13ff","path":"postinstall.js"}],"package_integrity":[{"filename":"r2-https-b-1.0.0.tgz","hashes":{"sha512_sri":"sha512-4awAT4uqWnfreXIQ2dwlO2rNOz66od0hf1qIosFZYyqaM1NoUZXnIhHnKZQedq5+aXdUJCwjiqiTqrnsbSO6qw==","sha1":"8a275bc95b24a3acaa524dcad29bc9007355fc19"}}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/@s4yhiitestpoc/r2-https-b/MAL-2026-17808.json"}}],"schema_version":"1.9.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}