CVE-2026-66747 ENDLESSDOORS: Zbtlink Router rctl/kworker Phone-Home Root Implant

Zbtlink router firmware ships an embedded remote-control implant, ENDLESSDOORS, present in every published build across the product line. It is the open-source ycsunjane/rctl tool built in as an OpenWrt package librctl.so, started at boot and run as root under the process name kworker to blend in...

CVE-2026-66747

The CVE describes a firmware implant in Zbtlink router firmware (ENDLESSDOORS) embedded as an OpenWrt package (librctl.so) that runs at boot as root under kworker. It does not listen for connections but phones home over cleartext TCP to a hardcoded C2 address on channels 7000/7001, with no authen...