MAL-2026-12076 Malicious code in tinkoff-cache-path (npm)

The package advertises itself as an in-memory cache utility, but index.js unconditionally requires compat.js on load, which acts as a dropper. compat.js selects a platform-specific endpoint from an obfuscated list of hosts assembled at runtime via Array.join (oob-worker.cf*.workers.dev and *.dl.well1.site), downloads an opaque native binary over HTTPS, and falls back to a DNS-TXT covert channel that queries a count record at c.<domain> and reassembles numbered base64 TXT chunks into an executable buffer. The payload is written under /var/tmp or %TEMP% with a disguised name (.cache<rand> on Unix, dotnet_diag<rand>.exe on Windows), chmod +x, and spawned detached via cp.spawn("/bin/sh", ["-c", fp + " &"], {detached:true}).unref() or spawn("cmd",…). A.analytics_state marker file and DO_NOT_TRACK-shaped environment opt-outs are used as cover. The declared purpose (caching) has no relationship to fetching and executing a native binary from attacker-controlled infrastructure.

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.