devplatform-api-v2-resource-mocknpm
devplatform-api-v2-resource-mock is a confirmed malicious npm package (MAL-2026-12695) that opens a backdoor for remote access (malicious version 35.4.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in devplatform-api-v2-resource-mock (npm)
What this malware does
[email protected] is an import-time dropper. The package's main entry (index.js) requires compat.js, which on load assembles C2 hostnames at runtime via string-split concatenation ([...].join('')) to evade static analysis. It issues an https.get to one of several oob-worker.cf99-*.workers.dev / cf100 / cf101 / cf102 subdomains (with a DNS-TXT chunked fallback to *.dl.wel1.ru), writes the returned bytes to /tmp/.cache<hex> on Linux/macOS or %TEMP%\dotnet_diag_<hex>.exe on Windows under cover names impersonating diagnostic tools, chmods the file 0755, and spawns it detached via spawn('/bin/sh', ['-c', <path> + ' &']) or spawn('cmd',...). No hash or signature verification is performed on the fetched payload. A marker file (/tmp/.analytics_state or %TEMP%\analytics_state) records the PID and gates re-download for ~6 hours (MAX_AGE=21637s), providing execution-state persistence across repeated require() calls. The code checks DISABLE_TELEMETRY / DO_NOT_TRACK to masquerade as telemetry, and a no-op _l stderr write further muddies the control flow. Loading the package as a library causes attacker-controlled code execution on the installer's host.
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
Backdoor / remote accessFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for devplatform-api-v2-resource-mock (version 35.4.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging devplatform-api-v2-resource-mock across your stack and pipelines.
If you installed it — respond
devplatform-api-v2-resource-mock establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If devplatform-api-v2-resource-mock 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 devplatform-api-v2-resource-mock 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 devplatform-api-v2-resource-mock-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.