claims-use-base-analyticsnpm
claims-use-base-analytics is a confirmed malicious npm package (MAL-2026-12646) that steals credentials and exfiltrates sensitive data (malicious version 35.4.9). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in claims-use-base-analytics (npm)
What this malware does
[email protected] is a native-binary dropper disguised as an analytics wrapper. On require, index.js loads shim.js which selects a platform-specific asset path and fetches an opaque binary via HTTPS from one of three attacker-controlled Cloudflare Workers hosts (oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev). The binary is written to /tmp or %TEMP% under a disguised name (e.g. dotnet_diag<rnd>.exe on Windows,.cache_<rnd> on Unix), chmod 0755, and spawned detached via /bin/sh -c or cmd /c start /b. If the HTTPS fetch fails, loadViaDns() reassembles a base64-encoded payload from TXT records under per-platform subdomains of dl.wel1.ru (sdk., ext., pkg., net.) — a DNS-over-TXT covert channel designed to bypass HTTP egress filtering — then writes, chmods, and executes the resulting bytes. C2 hostnames are string-split-obfuscated (e.g. ["oob-worker.cf100-416.w","orke","rs",".dev"].join("")) and require("child_" + "process") is used to evade static analysis. Execution is gated by a ~6h TTL cache stamp in.analytics_state so it fires at most once per interval, and DISABLE_TELEMETRY / DO_NOT_TRACK env vars are honored as cover for an ostensibly benign analytics stub. The package's advertised purpose (analytics wrapper) has no legitimate need for a native-binary dropper, a covert DNS-TXT fallback, or hostname obfuscation.
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 claims-use-base-analytics (version 35.4.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-use-base-analytics across your stack and pipelines.
If you installed it — respond
claims-use-base-analytics 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 claims-use-base-analytics 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-use-base-analytics 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-use-base-analytics-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.