{"id":"MAL-2026-12560","summary":"Malicious code in checkout-desktop-promocode (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (19310e46ffcb5a99a81bab29f7260407b9fb6af5af72bdd8f3b9f7819cc6ffda)\nOn require() of checkout-desktop-promocode, index.js loads _vendor.js which selects a per-platform endpoint, downloads a binary over HTTPS from obfuscated author-controlled hosts (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru, and oob-worker.cf*-*.workers.dev), with a DNS-TXT chunked base64 covert-channel fallback. The fetched bytes are written to /tmp or %TEMP% under an innocuous filename (.cache_\u003crand\u003e or dotnet_diag_\u003crand\u003e.exe), chmod 0755'd, and spawned detached via /bin/sh -c or cmd.exe. C2 hostnames are assembled at runtime by Array.join on fragment arrays (e.g. [\"oob-worker.cf99-9b3.w\",\"orker\",\"s.d\",\"ev\"].join(\"\")) to evade static string scanners, and log calls are stubbed to a no-op writer. The package advertises itself as a promocode SDK but ships none of that functionality; the only effect of importing it is arbitrary attacker code execution on the installer's host.\n","modified":"2026-08-05T14:35:24.019846961Z","published":"2026-08-05T14:12:31Z","database_specific":{"malicious-packages-origins":[{"source":"amazon-inspector","versions":["35.4.3"],"id":"IN-MAL-2026-015208","import_time":"2026-08-05T14:20:13.010721638Z","modified_time":"2026-08-05T14:12:31Z","sha256":"19310e46ffcb5a99a81bab29f7260407b9fb6af5af72bdd8f3b9f7819cc6ffda"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/checkout-desktop-promocode/v/35.4.3"}],"affected":[{"package":{"name":"checkout-desktop-promocode","ecosystem":"npm","purl":"pkg:npm/checkout-desktop-promocode"},"versions":["35.4.3"],"database_specific":{"indicators":{"evidence_files":[{"sha256":"2370ad07bdbfd5553407fd3f8d71dd30951a04a8634b2035f54797445a513b8e","tlsh":"98a1769915aa70188bb097e487174415f65ae6a337c0c2d4fb9c99881fb61348372efc","path":"_vendor.js"}],"package_integrity":[{"filename":"checkout-desktop-promocode-35.4.3.tgz","hashes":{"sha1":"9e59095255eadaae411fdc5f6dfec0feeeee3dff","sha512_sri":"sha512-udcDw4dSRO3LDQzSJo49PLDqKwpU+xeK3Z1J5bOdlsMBuotmVERMNuWyxshzFhgM1D3loq/YBrAHLdiU7ajk6g=="}}]},"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-desktop-promocode/MAL-2026-12560.json"}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}