This is starting to look like a very big deal - the error in the UPnP stack provided with the base Broadcom Board Support Package - which many OEM's skin for their brands - this bug allows for root privilege escalation from the WAN side of the device.
I don't have the CVE handy right now - thing is, the fix needs to come from the OEM to resolve this high risk security issue - this is a bigger deal than the WPS issue I brought up a few months back.
Vendors that may be affected:
- US Robotics
The vulnerability is located within the wanipc and wanppp modules of the Broadcom UPnP stack, which is used by manufacturers that deliver routers based on the Broadcom chipset.
A variety of routers have their UPnP interface available over the WAN interface, so the vulnerability can also be exploited over the Internet. It seems that, at the moment, the only popular UPnP implementation not hit by the remote preauth security vulnerability is MiniUPnP.
The remote preauth format string vulnerability in the Broadcom UPnP stack can be exploited to write arbitrary values to an arbitrary memory address, and also to remotely read router memory. When exploited, it allows an unauthenticated attacker to execute arbitrary code under the root account.
The vulnerability present in the SetConnectionType function of wanipc and wanppp modules can be reached with a single SOAP request that calls SetConnectionType function.
The format string vulnerability is present because the user-input from the SOAP request is supplied as a format string argument to the snprintf() function in wanipc.c and wanpp.c. The vulnerable code lines are located in the following files:
More info can be found here: