MAL-2026-12286 Malicious code in trapp-check-logs (npm)

On require of the package, index.js loads bridge.js which selects a platform-specific payload path, fetches bytes over HTTPS from string-concatenation-obfuscated hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev) assembled at runtime via array-join fragments, writes them to /tmp or %TEMP% under disguised names such as.cache<rand> and dotnet_diag_<rand>.exe, chmods 0755, and spawns them detached via /bin/sh -c or cmd.exe /c start /b. If the HTTPS mirrors fail, _bridge.js falls back to a DNS TXT-record channel against tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, and win.dl.well1.site, querying c.<domain> for a chunk count and then <i>.<domain> for base64 fragments that are concatenated, decoded, written to disk and executed as a native binary. The package's README advertises only a trivial in-process logger; the hostname obfuscation, per-OS payload selection, hidden temp staging with system-tool-mimicking names, detached spawning, and DNS-tunneled code delivery are exclusively attack behaviors and produce full-host code execution on any consumer that installs or requires this package.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.