boxy-mm-server-loader

{"modified":"2026-08-05T14:27:36Z","published":"2026-08-05T14:27:36Z","schema_version":"1.7.4","id":"MAL-2026-13070","summary":"Malicious code in boxy-mm-server-loader (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (26c25489d15bfaaf8e337af2f2fa446e86fdc8cc5fae3199be2451bdb35196ef)\nOn `require('boxy-mm-server-loader')`, index.js loads _polyfill.js, which fetches a platform-specific binary from one of three string-split-obfuscated Cloudflare Workers hosts (oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev), writes it to /var/tmp/.cache_<hex> on Unix or %TEMP%/dotnet_diag_<hex>.exe on Windows, chmods 0755, and spawns it detached via `/bin/sh -c` or `cmd.exe /c start /b`. A DNS TXT-record covert channel over c.<domain> / 0.<domain> / 1.<domain> against sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru acts as a delivery fallback: TXT chunks are concatenated and base64-decoded into the same write+chmod+spawn path. Destination hostnames and the `child_process` require are assembled from split character arrays via `.join(\"\")`; dropped artifacts use decoy names mimicking system telemetry (.cache_<hex>, dotnet_diag_<hex>.exe,.analytics_state). No hash or signature verification is performed on the fetched bytes.\n","affected":[{"package":{"ecosystem":"npm","name":"boxy-mm-server-loader"},"versions":["35.5.8"],"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":"c29296b8c7c067a6e6dfda30b6e147e011d7192869bf97a4712287c556de846f","tlsh":"0aa1b79a06a6701987b0dbe087174816f65ff6633380c284fb9c69985f7712483b2efc"}],"package_integrity":[{"filename":"boxy-mm-server-loader-35.5.8.tgz","hashes":{"sha1":"500a103c2166d0ad860a66e9f83983b459e3a862","sha512_sri":"sha512-95i+EO9qqAcVw7yIuS+hw++Vfo43eh7xiOZmKXD5iKQpxKtFhboZ9HDsUtk3fnOvNxjmQ0JUuVvp2lxPxDVL1w=="}}]}}}],"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/boxy-mm-server-loader/v/35.5.8"}],"credits":[{"name":"Amazon Inspector","type":"FINDER","contact":["inspector-research@amazon.com"]}],"database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-015309","import_time":"2026-08-05T15:19:44.042426019Z","modified_time":"2026-08-05T14:27:36Z","sha256":"26c25489d15bfaaf8e337af2f2fa446e86fdc8cc5fae3199be2451bdb35196ef","source":"amazon-inspector","versions":["35.5.8"]}]}}