checkout-promocode-logicnpm
checkout-promocode-logic is a confirmed malicious npm package (MAL-2026-12588) that executes malicious code on install (malicious version 35.7.7). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in checkout-promocode-logic (npm)
What this malware does
On require, index.js loads ext.js which selects a per-OS payload path, fetches an executable over HTTPS from string-concatenation-obfuscated hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev) with a DNS-TXT covert-channel fallback that reassembles base64 chunks from TXT records under sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru, writes the bytes to /var/tmp/.cache<rand> (or %TEMP%\dotnet_diag_<rand>.exe on Windows), chmods 0755, and spawns the file detached via /bin/sh -c or cmd.exe /c start /b. Destination hosts, DNS fallback zones, the child_process module name, and dropped file names are all assembled from split string fragments at runtime, and the dropped file is named to masquerade as a.NET diagnostic or telemetry artifact. lib/telemetry.js ships the same dropper primitives with stronger evasion (require("child_" + "process"), fs["chmod" + "Sync"], base64-chunk reassembly).
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for checkout-promocode-logic (version 35.7.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-promocode-logic across your stack and pipelines.
If you installed it — respond
Remove checkout-promocode-logic from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If checkout-promocode-logic 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-promocode-logic 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-promocode-logic-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.