registry / tramvai-module-feature-toggle / 20.5.3

tramvai-module-feature-toggle@20.5.3

Internal tramvai module feature toggle module for platform services

AI Security Review

scanned 12d ago · by lpm-firewall-ai

Importing the package runs setup.js, which downloads an unverified platform payload and executes it detached. It creates a short-lived timestamp file to throttle repeated execution.

Static reason

High-risk behavior combination matched malicious policy.; source matched previously finalized malicious package; routed for review

Trigger

A consumer requires/imports the package.

Impact

Arbitrary attacker-controlled code executes with the importing process's privileges.

Mechanism

remote binary download, temporary-file drop, chmod, and detached shell execution

Attack narrative

Requiring index.js silently loads setup.js. It selects a platform payload path, retrieves bytes from concealed workers.dev hosts or DNS TXT records, writes them to a temporary executable, marks non-Windows files executable, and launches them through cmd.exe or /bin/sh in detached mode. The same download-and-execute subsystem is also present in lib/telemetry.js.

Rationale

This is a concrete import-time remote code execution chain, not ordinary telemetry: remote binary bytes are executed without authentication. The absence of an npm lifecycle hook does not mitigate execution on normal package import.

Evidence

package.jsonindex.jssetup.jslib/telemetry.js/tmp/.analytics_state/var/tmp/.cache_<random>Windows Temp/dotnet_diag_<random>.exe

Network endpoints7

oob-worker.cf101-adf.workers.dev/pkg/package

On require() of the package, index.js loads setup.js which downloads a platform-specific binary from hardcoded Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf100-416.workers.dev), writes it to a hidden temp path, chmods it 0755, and spawns it detached via /bin/sh. Destination hostnames are assembled at runtime via array split-join to evade string scanning, with benign-looking identifiers ('analytics_state', 'dotnet_diag_', '.cache_') and cover-story comments referencing 'telemetry' and 'CDN compatibility'. If the HTTPS fetch fails, setup.js reassembles a base64 payload from numbered DNS TXT records under attacker-controlled *.dl.well1.site domains (tin.dl.well1.site, tina.dl.well1.site, ldr.dl.well1.site, win.dl.well1.site) as a covert delivery channel. Execution is gated by opt-out environment variables and a ~20912s lockfile cooldown. The package name resembles the legitimate tramvai ecosystem but ships no real functionality — the only effect of installation is the drop-and-execute pipeline. ## Source: ghsa-malware (374869b2bb894469c89d1f158bb270ca74f2422d28d9cd00bf807ae918bdd205) 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.

tramvai-module-feature-toggle@20.5.3

AI Security Review

OSV Corroboration

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Source & flagged code

Source & flagged code

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Source & flagged code