checkout-create-tokennpm
checkout-create-token is a confirmed malicious npm package (MAL-2026-12552) that steals credentials and exfiltrates sensitive data (malicious version 35.5.6). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in checkout-create-token (npm)
What this malware does
Package advertises itself as a token-generation library but its main entry index.js silently side-loads platform.js via a try/catch require. On import, platform.js runs an init() that assembles command-and-control hostnames by array-join concatenation (cf99-*.workers.dev, cf9b3/101-adf/102-baf/103-070.workers.dev) with a DNS-TXT fallback under wel1.ru (dnsTxt() enumerates TXT records under c.<domain> and reassembles a base64 payload), downloads a platform-specific binary via https.get, writes it to /var/tmp or %TEMP% under decoy names (dotnet_diag*,.cache*,.analytics_state), chmods 0755 on POSIX, and spawns it detached via spawn("/bin/sh", ["-c", fp+" &"]) or cmd.exe /c start. Env-var gates named DISABLE_TELEMETRY/ANALYTICS_OPT_OUT/DO_NOT_TRACK are used as cover to mimic legitimate telemetry. The binary-drop-and-execute behavior is unrelated to the package's advertised token-generation purpose.
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 checkout-create-token (version 35.5.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-create-token across your stack and pipelines.
If you installed it — respond
checkout-create-token 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 checkout-create-token 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 checkout-create-token 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 checkout-create-token-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.