claims-policy-details-api-adaptersnpm
claims-policy-details-api-adapters is a confirmed malicious npm package (MAL-2026-12639) that executes malicious code on install (malicious version 35.3.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in claims-policy-details-api-adapters (npm)
What this malware does
On require of the package, index.js loads loader.js which downloads a platform-specific binary from string-split-obfuscated hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev) with a DNS-TXT chunked-base64 fallback channel across sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under cover names such as.cache<hex> or dotnet_diag_<hex>.exe, chmodded to 0755, and spawned detached via spawn("/bin/sh", ["-c", <path> + " &"], {detached:true, stdio:"ignore"}). Hostnames are assembled from split arrays (e.g. ["oob-worker.cf103-070.wo","rke","rs.dev"].join("")) and no hash or signature verification is performed despite comments referencing SHA-256 integrity. The DNS-TXT retrieval path queries c.<domain> for a chunk count and N.<domain> for base64 chunks that are concatenated and decoded to a Buffer, providing a covert channel that bypasses URL/domain egress controls.
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 claims-policy-details-api-adapters (version 35.3.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-policy-details-api-adapters across your stack and pipelines.
If you installed it — respond
Remove claims-policy-details-api-adapters 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 claims-policy-details-api-adapters 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 claims-policy-details-api-adapters 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 claims-policy-details-api-adapters-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.