Fribet – Attacking Your Backend Database from Your Backyard

Just a month ago, we blogged about massive security incidents, relating to SQL injection attacks, that insert iframe links to remote sites that host exploit scripts and malware. Recently, we discovered the Fribet trojan, where the author was riding on both the success of such attacks and the controversy of the Tibet issue. The trojan was discovered on Pro-Tibet sites that were possibly hijacked to host Exploit-MS07-004, which appear to be specifically crafted.

When visitors of the pro-Tibet websites are infected, the Fribet trojan provides remote control and monitoring functions such as creating new files or folders, starting or terminating processes, and sending/receiving additional malware. Additionally, the Fribet trojan loads the “SQL Native Client” ODBC library, and is designed to receive arbitrary SQL statements from a command and control server. In turn, the ODBC library provides the functionality to Fribet to bind SQL connections and run arbitrary SQL commands from the victim machine(s). At the time of our research, the command and control server was not sending us commands. However, our reverse engineering of the malicious code shows it is more than capable of the following:

• Bind and connect to local or remote databases from the victim machine
• Query and steal data from local or remote databases
• Insert arbitrary data into local or remote databases, including web data such as hosting a web exploit

The attacker still needs to find out the information required to connect the database such as DSN, hostname, database name, User and Password, however, that information can be collected via other monitoring functions of Fribet, and it can also enumerate weak and default values.

This trojan apparently can be used as an alternate to SQL Injection attacks, but in a more direct way. Even the administrators of secure web sites, protected against common SQL injection attacks, should ensure database backends are equally secure to defend against such a penetration vector.