{"id":"MAL-2026-12749","summary":"Malicious code in devplatform-s3-uploader (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (202bd53eb339cdbd72320893af375903622c29dc8f55c54c6dc9ae94d2e727b9)\nOn require() of the package, index.js loads _helpers.js which unconditionally runs a start() routine that selects a platform-specific asset path, fetches an opaque native binary from one of four hardcoded Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, cf100-416.workers.dev, cf101-adf.workers.dev, cf102-baf.workers.dev), with a DNS-TXT fallback that reassembles base64 chunks from sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to a temp path under a cover-story name (e.g. dotnet-diag under /var/tmp or TEMP), chmod 0755, then executed detached via spawn('/bin/sh', ['-c', path + ' &']) or spawn('cmd',...) on Windows. No hash or signature verification. Network destinations are not the package publisher and are unrelated to the advertised 'S3 uploader' purpose. Host names and API identifiers are constructed by string-split/array-join (e.g. ['oob-worker.cf100-416.workers.','de','v'].join(''), require('child_' + 'process'), fs['chmod' + 'Sync']) to evade static analysis. A secondary module lib/telemetry.js, presented as an 'analytics SDK', ships parallel dropper primitives (base64 chunk reassembly, bracket-obfuscated chmod to 0755, cp.spawn('/bin/sh', ['-c', filePath + ' &'], {detached:true})) — co-shipped fallback attack infrastructure.\n","modified":"2026-08-05T14:36:54.101173275Z","published":"2026-08-05T13:44:04Z","database_specific":{"malicious-packages-origins":[{"sha256":"202bd53eb339cdbd72320893af375903622c29dc8f55c54c6dc9ae94d2e727b9","source":"amazon-inspector","versions":["35.4.4"],"id":"IN-MAL-2026-015018","import_time":"2026-08-05T14:19:53.132331733Z","modified_time":"2026-08-05T13:44:04Z"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/devplatform-s3-uploader/v/35.4.4"}],"affected":[{"package":{"name":"devplatform-s3-uploader","ecosystem":"npm","purl":"pkg:npm/devplatform-s3-uploader"},"versions":["35.4.4"],"database_specific":{"indicators":{"evidence_files":[{"sha256":"2487344ad3c8305c16a9247dca3f03212486b5dfcdeaa69f8d02b23d6c9f9c12","tlsh":"6aa1a85a16a6701987b0d7e4c6174419f65be6633380c2d8fb5ca5941f7351483b2efc","path":"_helpers.js"},{"sha256":"151bbc6fe0b458437d3fe6766a8f36e116f0459ad9abfd49c339285db0e09ac3","tlsh":"1f835056566a142186b2b368df234107ff3685272643429dbafc82dc1fbd72092a5ffc","path":"lib/telemetry.js"}],"package_integrity":[{"hashes":{"sha1":"a5635cc3e0fd6d126eac38540cc71ba285edf404","sha512_sri":"sha512-z7eVQz/zwCmlTe6XBqucPYHnYxqtb3FNySaKjpJvR4ATDgssQ/vNIlOtvyuviM3Zf4Xuw2pCP0/S3oS+t6jCsQ=="},"filename":"devplatform-s3-uploader-35.4.4.tgz"}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/devplatform-s3-uploader/MAL-2026-12749.json","cwes":[{"name":"Embedded Malicious Code","cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature."}]}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}