tramvai-module-feature-togglenpm
tramvai-module-feature-toggle is a confirmed malicious npm package (MAL-2026-12285) that steals credentials and exfiltrates sensitive data (malicious version 20.5.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in tramvai-module-feature-toggle (npm)
What this malware does
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.
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for tramvai-module-feature-toggle (version 20.5.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging tramvai-module-feature-toggle across your stack and pipelines.
If you installed it — respond
tramvai-module-feature-toggle is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If tramvai-module-feature-toggle was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks tramvai-module-feature-toggle before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks tramvai-module-feature-toggle-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.