Malicious code in tcb-web-images (npm)

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Source: amazon-inspector (1e4ea2872f88d974e66cc870c5fbfbf92294eb63026155a96bea567a096f4d69)

On require('tcb-web-images'), index.js loads _helpers.js which immediately runs a setup routine that selects an OS/arch-specific URL path and downloads a binary over HTTPS from one of four Cloudflare Workers hosts whose names are assembled at runtime by joining string-array fragments (oob-worker.cf103-070.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev), with a DNS-TXT chunked fallback under *.dl.well1.site. The downloaded bytes are written to /var/tmp or %TEMP% under disguised names mimicking system utilities (.cache_<rand> on Unix, dotnet_diag_<rand>.exe on Windows), chmod'd 0755, and detach-spawned via /bin/sh -c '<path> &' or cmd.exe. A freshness marker is stored as .analytics_state and stderr is silenced by a no-op logger. A second, larger copy of the same dropper is shipped as lib/telemetry.js under an 'analytics SDK' cover story, using additional string-concatenation obfuscation (require("child_" + "process"), fs["chmod"+"Sync"]); it is not referenced by the current index.js but is bundled at the tarball root. The package is advertised as a 'lightweight images wrapper' — the dropper behavior is unrelated to that purpose, the destinations are author-controlled and obfuscated to defeat scanners, and the delivered bytes are an opaque native executable with no publisher provenance, integrity check, or version pinning.

Source: ghsa-malware (c1380a3b63e9f71c1a3d2d58040216fe5ffc0a0b27291d8d4596224f1ee6aa64)

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.