Some Internet router devices incorrectly accept UPnP requests over the WAN interface.
Universal Plug and Play (UPnP) is a networking protocol mostly used for personal computing devices to discover and communicate with each other and the Internet. Some UPnP enabled router devices incorrectly accept UPnP requests over the WAN interface. "AddPortMapping" and "DeletePortMapping" actions are accepted on these devices. These requests can be used to connect to internal hosts behind a NAT firewall and also proxy connections through the device and back out to the Internet. Additional details can be found in Daniel Garcia's whitepaper, "Universal plug and play (UPnP) mapping attacks". [PDF] A list of devices reported to be vulnerable can be found on the UPnP hacks website.
A remote unauthenticated attacker may be able to scan internal hosts or proxy Internet traffic through the device.
Contact the device's vendor to find out if a firmware update is available to address this vulnerability.
Disable UPnP on the device.
Thanks to Daniel Garcia for reporting this vulnerability.
This document was written by Jared Allar.
|Date First Published:||2011-10-05|
|Date Last Updated:||2012-11-30 17:58 UTC|