Yealink SIP-T46U Web FastCGI Service tftpuploadiperf mod_webd.TFTPUploadIperf command injection

A vulnerability was identified in Yealink SIP-T46U 108.86.0.118. Affected by this vulnerability is the function mod_webd.TFTPUploadIperf of the file /api/inner/tftpuploadiperf of the component Web FastCGI Service. The manipulation of the argument ip/port leads to command injection. The attack needs to be initiated within the local network. The exploit is publicly available and might be used. Upgrading to version 108.87.0.23 addresses this issue. Upgrading the affected component is recommended. The vendor explains: "It has been fixed (...) for our technical support branch. However, please note that this specific support branch firmware is not publicly released yet."