[Description]
On Verizon 5G Home LVSKIHP InDoorUnit (IDU) 3.4.66.162 and OutDoorUnit (ODU) 3.33.101.0 devices, the CRTC and ODU JSON endpoints rely on a static jrpc account username/password for access control. This password can be generated via a binary included in the firmware, after ascertaining the MAC address of the IDU's base Ethernet interface, and adding the string DEVICE_MANUFACTURER='Wistron_NeWeb_Corp.' to /etc/device_info to replicate the host environment. This occurs in /etc/init.d/wnc_factoryssidkeypwd (IDU).

[Additional Information]
This vulnerability has been patched on firmware 5.4.91.162 (IDU) and 5.33.141.0 (ODU). The firmware download location can be ascertained from the upgrade logs within a device.

[Vulnerability Type]
Use of Hard-coded Credentials

[Vendor of Product]
Verizon / Wistron Neweb Corporation

[Affected Product Code Base]
Verizon 5G Home Internet Modem/Router LVSKIHP - 3.4.66.162 (IDU)

[Affected Component]
Line 162 of InDoorUnit /etc/init.d/wnc_factoryssidkeypwd: 
   rpc_pwd=`/usr/sbin/wnc_get_sec_2 $baseMAC`

[Attack Type]
Remote

[Impact]
Escalation of Privileges
Information Disclosure

[Attack Vectors]
An attacker must extract the binary from the firmware image, run it in an ARM environment with the string "DEVICE_MANUFACTURER='Wistron_NeWeb_Corp.'" in a file /etc/device_info, and provide the IDU's base ethernet MAC address.

[Discoverer]
Matthew Lichtenberger, Shea Polansky