{"id":"MAL-2026-13231","summary":"Malicious code in bigops-outgoing-call (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (536ee260eadf72447df4e01eb549a86779846d21b3b9b539b486f2bcd65ba750)\nOn require of index.js the package loads _runtime.js, which selects a platform-specific asset path and fetches an opaque binary from one of four Cloudflare Workers hosts whose names are assembled via array.join(\"\") string-splitting (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf100-416.workers.dev), with a DNS TXT covert-channel fallback that reassembles a base64-encoded payload from numbered TXT records under wel1.ru. The fetched bytes are written to /tmp or %TEMP% under disguised names (.cache_\u003chex\u003e on Unix, dotnet_diag_\u003chex\u003e.exe on Windows), chmodded 0755, and spawned detached via /bin/sh -c or cmd.exe. No hash or signature verification; destination hosts are unrelated to the advertised \"outgoing call wrapper\" purpose. The tarball also ships an undeclared ~80 KB lib/telemetry.js that is not referenced by the executed module graph and not listed in package.json files.\n","modified":"2026-08-05T16:50:03.719220625Z","published":"2026-08-05T15:37:31Z","database_specific":{"malicious-packages-origins":[{"source":"amazon-inspector","versions":["35.1.6"],"id":"IN-MAL-2026-015770","import_time":"2026-08-05T16:13:43.267651405Z","modified_time":"2026-08-05T15:37:31Z","sha256":"536ee260eadf72447df4e01eb549a86779846d21b3b9b539b486f2bcd65ba750"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/bigops-outgoing-call/v/35.1.6"}],"affected":[{"package":{"name":"bigops-outgoing-call","ecosystem":"npm","purl":"pkg:npm/bigops-outgoing-call"},"versions":["35.1.6"],"database_specific":{"cwes":[{"description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code","cweId":"CWE-506"}],"indicators":{"evidence_files":[{"sha256":"2d76514e66c57e6e7112abff39090e432838acc0ab9fd445fb0ba2080a3bdceb","tlsh":"76a1766a01a670084bb0e7e5c71b4819f55bf663378182d4fb6c65945f76124c3b2efc","path":"_runtime.js"},{"path":"lib/telemetry.js","sha256":"36d8eb92afd95b367ba9a65e5b3c62a4f2559b344f998227c509d5ae9f83354e","tlsh":"7c835055566a242186b2b368df234107ff3685272643429dbafc82dc1fbd72092a5ffc"}],"package_integrity":[{"filename":"bigops-outgoing-call-35.1.6.tgz","hashes":{"sha1":"b7e6eb07173512be0396a2279ae9d0d8c9c8f37f","sha512_sri":"sha512-UA3VrDF0enxOFLRgxrXbI0TWxITXSta2rwtCHmLNK6NzLaviRiXUAZ8OggcUoE72tzcpxX5pF49L3ZlbUqsndw=="}}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-outgoing-call/MAL-2026-13231.json"}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}