bigops-legacy-utils

{"modified":"2026-08-05T15:38:27Z","published":"2026-08-05T15:38:27Z","schema_version":"1.7.4","id":"MAL-2026-13222","summary":"Malicious code in bigops-legacy-utils (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (7bb10772ad63d0dbea89e74d3ad56deb097746551202cae3fb1a253b42ca11e0)\nOn require('bigops-legacy-utils'), index.js loads _polyfill.js which selects a platform-specific payload path, downloads opaque binary bytes from hardcoded Cloudflare workers.dev subdomains (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev) with a DNS-TXT base64 fallback under *.dl.wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), writes the payload to /var/tmp or %TEMP% under disguised names (.cache_<suffix> on POSIX, dotnet_diag_<suffix>.exe on Windows), chmods 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start /b. Destination hostnames are reassembled from split string fragments (e.g. ['sdk.dl.w','el1.ru'].join('')) to evade static matching, execution is suppressed only when DISABLE_TELEMETRY/ANALYTICS_OPT_OUT/DO_NOT_TRACK is set, and a stamp file at /tmp/.analytics_state throttles re-runs. Comments label the code as 'polyfill'/'analytics' as cover.\n","affected":[{"package":{"ecosystem":"npm","name":"bigops-legacy-utils"},"versions":["35.2.6"],"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":[{"path":"_polyfill.js","sha256":"7b01250be38ffd64fc651f0cf955beba626a81fd0a97558198e9128e2c233d34","tlsh":"bda1a69a12a9701887b0a7e4c7175416f657f6633781c298fb6ca5c81fb2524c3b2efc"}],"package_integrity":[{"filename":"bigops-legacy-utils-35.2.6.tgz","hashes":{"sha1":"3b91e984ffbb34182617a7f9e4ebf90e5d1bd8aa","sha512_sri":"sha512-r0alKIiAjbIUOEkqkUBAx7MMhduk0p9W9HeY0Tk9138E9rS7dkC9o705BEmPwYh2peEar2C6BD640IGCtlst5g=="}}]}}}],"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/bigops-legacy-utils/v/35.2.6"}],"credits":[{"name":"Amazon Inspector","type":"FINDER","contact":["inspector-research@amazon.com"]}],"database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-015776","import_time":"2026-08-05T16:13:44.099598422Z","modified_time":"2026-08-05T15:38:27Z","sha256":"7bb10772ad63d0dbea89e74d3ad56deb097746551202cae3fb1a253b42ca11e0","source":"amazon-inspector","versions":["35.2.6"]}]}}