Filtered by vendor Zbtlink Subscriptions
Filtered by product We5931 Firmware Subscriptions
Total 1 CVE
CVE Vendors Products Updated CVSS v3.1
CVE-2026-66747 1 Zbtlink 20 Cpe2801 Firmware, We1026-5g-wd Firmware, We1326 Firmware and 17 more 2026-08-05 9.8 Critical
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 with the kernel's [kworker/*] threads. It opens no listening port; it phones home over cleartext TCP to a hardcoded command-and-control server (command channel 7000, interactive-shell callback 7001) with no authentication and no transport encryption, re-attempting contact roughly every 35 seconds. Its command handler passes any received string to popen() as uid=0, and a reserved rctlbash command returns an interactive root shell. Because the channel is unauthenticated and cleartext, control is not limited to whoever planted it: any party that answers at the C2 address, occupies the network path (DNS or route hijack), or acquires the hardcoded fallback domain obtains unauthenticated remote code execution as root.