The bigops-tinkoff-telephony-mock npm package (version 35.5.1) contains malicious code that, upon require(), loads a runtime script which fetches a platform-specific binary from Cloudflare Workers hosts reconstructed at runtime from split string fragments, with a fallback covert DNS TXT channel. The fetched binary is saved to temporary directories under disguised filenames, made executable, and run detached via shell commands. No hash or signature verification is performed, and the hosts are unrelated to the package publisher. Additionally, a fake telemetry SDK bundled in the package contains the same dropper. This results in full remote code execution on any machine that installs or imports the package.

Systems that install or run this package are fully compromised, as the malicious code executes arbitrary binaries with no verification. This can lead to complete system takeover, exposure of secrets and keys stored on the machine, and persistent unauthorized access. Removal of the package alone does not guarantee eradication of all malicious components.

Remove the bigops-tinkoff-telephony-mock package version 35.5.1 immediately from all affected systems. Rotate all secrets and keys stored on compromised machines from a secure, unaffected environment. Because the package executes arbitrary code without verification, assume full system compromise and perform thorough incident response and remediation. No official patch or fix is available; avoid using this package version entirely.