{"id":"MAL-2026-13044","summary":"Malicious code in boxy-fixture (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (bb575dd1ac71dc5968106b313680bb84dd0d90172e82c1a79887b085ba55b4bd)\nOn require() of the package, index.js loads _support.js which executes setup() at module load. The code reconstructs Cloudflare Workers hostnames (oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev) from split-string arrays, downloads a platform-specific binary via https.get, writes it to /var/tmp/.cache_\u003chex\u003e on Unix or %TEMP%\\dotnet_diag_\u003chex\u003e.exe on Windows, chmods it 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start with unref(). A DNS-TXT covert-channel fallback reconstructs the payload from base64-encoded TXT records under sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru (chunk count from c.\u003cdomain\u003e, chunks from \u003ci\u003e.\u003cdomain\u003e). A second copy of the dropper primitives (base64 chunk assembly, chmodSync 0755 via string concatenation, detached /bin/sh -c spawn) is bundled in lib/telemetry.js under an 'Analytics SDK' label. Filenames masquerade as analytics_state and dotnet_diag_*.exe.\n","modified":"2026-08-05T15:51:58.264093945Z","published":"2026-08-05T14:31:37Z","database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-015335","import_time":"2026-08-05T15:19:45.491790555Z","modified_time":"2026-08-05T14:31:37Z","sha256":"bb575dd1ac71dc5968106b313680bb84dd0d90172e82c1a79887b085ba55b4bd","source":"amazon-inspector","versions":["35.6.4"]}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/boxy-fixture/v/35.6.4"}],"affected":[{"package":{"name":"boxy-fixture","ecosystem":"npm","purl":"pkg:npm/boxy-fixture"},"versions":["35.6.4"],"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":"05a1955a16a670198bb097e0c7175417f66bf6633780c6c4f69ca9940f726248372efc","path":"_support.js","sha256":"69b8e1204fe3fce756545786daf8e60a00739007b734a880411a1355c67235e2"},{"path":"lib/telemetry.js","sha256":"87d3d44ed7e6483aac86ad3ad13a0d3cf2badb96ff904e7e5887bd5a289ccfe7","tlsh":"1c835055566a242186b2b368df234107ff3685272643429dbafc82dc1fbd72092a5ffc"}],"package_integrity":[{"hashes":{"sha512_sri":"sha512-in1QuEjx06VJnXGSpdgbM5Lb3l7otaMpN/phdaKZwNF35/8TxVH10fMPt7YnwHLGjywyxEkNszlWN3PkhC5BhQ==","sha1":"3198af09eaa925499a3c3d012193303261952e04"},"filename":"boxy-fixture-35.6.4.tgz"}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/boxy-fixture/MAL-2026-13044.json"}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}