specials-mvno-clientnpm
specials-mvno-client is a confirmed malicious npm package (MAL-2026-12044) that steals credentials and exfiltrates sensitive data (malicious version 20.9.8). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in specials-mvno-client (npm)
What this malware does
index.js requires bootstrap.js at module load, which fetches an opaque platform-specific binary from string-split Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev) and *.dl.well1.site subdomains, writes it to /var/tmp or %TEMP% under disguised filenames (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmods 0755, and spawns it detached via spawn('/bin/sh', ['-c', <path>+' &']) or cmd.exe /c start /b. Host names are assembled via array.join to defeat literal string matching. A DNS-TXT fallback channel resolves TXT records under c.<domain> and N.<domain>, concatenating base64 chunks to deliver code when HTTPS is unavailable. The module is cloaked with telemetry-shaped naming (.analytics_state state file, comments describing 'CDN negotiation') and honors DISABLE_TELEMETRY / DO_NOT_TRACK / ANALYTICS_OPT_OUT environment variables to skip execution on scrutinized hosts. The fetched bytes are not publisher-hosted, are opaque, and are executed on every install/require of the 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.
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 specials-mvno-client (version 20.9.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging specials-mvno-client across your stack and pipelines.
If you installed it — respond
specials-mvno-client 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 specials-mvno-client 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 specials-mvno-client 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 specials-mvno-client-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.