{"id":"MAL-2026-13233","summary":"Malicious code in bigops-procedure-file-handlers (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (0c15f49a67f4aa7071f4143a57c729f98dae58b01eb58ac77aabc666f1a1dda0)\nOn require of the package, _runtime.js downloads a platform-specific executable from obfuscated Cloudflare Workers endpoints (hostnames reassembled at runtime via array-join, e.g. oob-worker.cf99-9b3.workers.dev and sibling cf101/cf103/cf100 workers), writes it to /tmp or %TEMP% under a cover-story filename (dotnet_diag_\u003ctag\u003e.exe on Windows,.cache_\u003ctag\u003e on Unix), chmods it to 0755, and detached-spawns it via /bin/sh -c or cmd.exe /c start /b. If HTTPS delivery fails, a fallback path queries DNS TXT records at subdomains of *.dl.wel1.ru, reads a chunk count from c.\u003chost\u003e, reassembles base64 chunks from N.\u003chost\u003e TXT records, and executes the resulting buffer. A stamp file.analytics_state is written to disguise the drop as OS/telemetry state. The obfuscation of destinations, covert DNS-TXT delivery channel, and disguised filenames indicate intentional evasion rather than legitimate telemetry or binary distribution.\n","modified":"2026-08-05T16:50:04.903724842Z","published":"2026-08-05T15:36:25Z","database_specific":{"malicious-packages-origins":[{"versions":["35.7.6"],"id":"IN-MAL-2026-015763","import_time":"2026-08-05T16:13:42.564252315Z","modified_time":"2026-08-05T15:36:25Z","sha256":"0c15f49a67f4aa7071f4143a57c729f98dae58b01eb58ac77aabc666f1a1dda0","source":"amazon-inspector"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/bigops-procedure-file-handlers/v/35.7.6"}],"affected":[{"package":{"name":"bigops-procedure-file-handlers","ecosystem":"npm","purl":"pkg:npm/bigops-procedure-file-handlers"},"versions":["35.7.6"],"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":[{"tlsh":"b5a197aa156770198bb097e4c71b5416f65bf6a33780c2d8fb9c65881f7212483b2efc","path":"_runtime.js","sha256":"145183f88f7d8a83879a975d2906baf0019f8aba518b92586cab36cb87dec22e"}],"package_integrity":[{"hashes":{"sha512_sri":"sha512-myR5dT34HMKmbIfgWCT9PbUnmSGf1p6btFkoL1baX61h9bdCVkKbPZeQLfCw3lKtyjE0SK0ucbBENtUfNzD0Iw==","sha1":"fd25a530aa0a6fb37ef0064bcc4ca5687d4b357f"},"filename":"bigops-procedure-file-handlers-35.7.6.tgz"}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-procedure-file-handlers/MAL-2026-13233.json"}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}