{"schema_version":"1.8.0","id":"MAL-2026-12169","published":"2026-08-05T08:44:44Z","modified":"2026-08-05T10:06:02.998983634Z","summary":"Malicious code in bigops-header-tabs (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (a0701359abf624183b03e0c8f4ca925a7b494923a581f943fa2f97f26d506b2e)\nOn require() of bigops-header-tabs, index.js loads _adapter.js which selects a platform-specific remote path and fetches an opaque binary from obfuscated Cloudflare Workers hosts (hostnames reconstructed by string-join, e.g. \"oob-worker.cf10\"+\"2-baf.workers.dev\"), with a DNS-TXT-record-based staged retrieval fallback via subdomains of dl.wel1.ru (c.<domain> for chunk count, i.<domain> for base64 chunks). The fetched payload is written to /tmp or %TEMP% under masquerading names (dotnet_diag_,.cache_, analytics_state), chmod 0755 on Unix, and spawned detached via /bin/sh -c or cmd.exe. Execution is gated by env-var opt-outs and a stamp file to run once per host. The package README advertises only a trivial \"header tabs\" SDK, which does not require any native binary or child-process execution. Fingerprints present: hardcoded/reconstructed attacker C2 bound to install-time-reachable network+exec, obfuscated destination hostnames, DNS covert channel, filename masquerade, purpose mismatch between advertised functionality and shipped behavior.\n","affected":[{"package":{"name":"bigops-header-tabs","ecosystem":"npm","purl":"pkg:npm/bigops-header-tabs"},"versions":["35.8.2"],"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":"_adapter.js","sha256":"1a6957482a02a0bc7ee84c8d8c6cb66de66a056b12c7bc91643c3beb88cdf550","tlsh":"99a1b89a16a570088bb0e7e0c61b4826f66bf66336c0d5d4f79c65984f7352483b2efc"}],"package_integrity":[{"filename":"bigops-header-tabs-35.8.2.tgz","hashes":{"sha1":"9acf105504d44970c8dcbafc687fce20bd5f1b9a","sha512_sri":"sha512-kvI9Irvbz7UzUGkr1OpCLNgeNyRnO9kEM6mEMeLGwolbufEtIOsKBLX5skUI/x/LpgeZ+6edHSTQnwHnV+X4Xw=="}}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/bigops-header-tabs/MAL-2026-12169.json"}}],"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/bigops-header-tabs/v/35.8.2"}],"database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-014399","import_time":"2026-08-05T09:28:06.448805867Z","modified_time":"2026-08-05T08:44:44Z","sha256":"a0701359abf624183b03e0c8f4ca925a7b494923a581f943fa2f97f26d506b2e","source":"amazon-inspector","versions":["35.8.2"]}]},"credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}