Software Engineering Institute

The Cisco Network Services (CNS) NetFlow Collection Engine (NFC) is a software package for supported UNIX platforms and is used to collect and monitor NetFlow accounting data for network devices such as routers and switches. It includes a web-based interface to perform application maintenance, configuration, and troubleshooting.

Versions of NFC prior to 6.0 create and use default accounts with an identical username and password of "nfcuser".

A remote attacker with knowledge of the default account information can gain administrative control of the NFC application configuration through the web-based interface.
For some configurations, the attacker may also be able to gain user access to the host operating system with the privileges of nfcuser. This access may allow for additional privilege escalation attacks on an affected system.

Change passwords for the affected account
Cisco has published instructions for changing the passwords on the nfcuser account in Cisco Security Advisory cisco-sa-20070425-nfc. This advisory contains additional information about how the issue has been addressed in newer versions of the affected software. Note that both the web-based and UNIX user account passwords must be changed on some platforms.