LWA-2026-10121 MAL-2026-12847 ↗ confirmed malware

bigops-tinkoff-telephony-mock@35.5.1

Malicious code in bigops-tinkoff-telephony-mock (npm)

T1059.007 · JavaScriptT1105 · Ingress Tool TransferT1071.001 · Web ProtocolsT1102 · Web ServiceT1082 · System Information DiscoveryT1059 · Command and Scripting Interpreter

Analysis

On require, the package loads a bundled downloader (_runtime.js) that fetches a platform-specific binary payload over HTTPS from Cloudflare Workers hosts oob-worker[.]cf102-baf[.]workers[.]dev, oob-worker[.]cf101-adf[.]workers[.]dev, oob-worker[.]cf100-416[.]workers[.]dev, and oob-worker[.]cf103-070[.]workers[.]dev (paths /pkg/package, /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe), with a fallback DNS-TXT channel via c[.]sdk[.]dl[.]wel1[.]ru (and ext[.]dl[.]wel1[.]ru, pkg[.]dl[.]wel1[.]ru, net[.]dl[.]wel1[.]ru). The downloaded binary is written to /var/tmp/.cache_<hex> (or dotnet_diag_<hex>.exe in the temp dir on Windows), made executable, and launched detached in the background via /bin/sh -c '<path> &' or cmd.exe /c start /b. A stamp file at /tmp/.analytics_state throttles re-execution. This is remote binary download-and-execute at package load time.

analyzed by
Leitwacht
first seen
Aug 5, 2026, 12:59 PM
analyzed
Aug 5, 2026, 01:08 PM

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Independently detected by the Leitwacht supply-chain probe. IOCs are defanged. Published CC0. Think this is a mistake? See the dispute policy.