boxy-mm-server-loader @35.5.8
Vulnerability report · Last retrieved from osv.dev August 19, 2026 at 10:51 AM UTC
OSV ID
MAL-2026-13070
Ecosystem
npm
Summary
On 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.
Source: amazon-inspector (26c25489d15bfaaf8e337af2f2fa446e86fdc8cc5fae3199be2451bdb35196ef)
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