So you think you patch everything regularly and watch out for zero days and take preventive actions. You have anti-virus running on all of your 5 desktops and laptops and have convinced your spouse to be careful as well.
But did you forget your modem ?
All too often network equipment devices are forgotten – once installed and configured, most users or businesses do not worry about applying firmware updates provided by manufacturers. Even the simplest failure can affect thousands of users, who are silently attacked and prompted to inadvertently install malware or steered into phishing domains. As pointed out by the researcher Marta Janus, DSL modems are attacked by different kinds of malware, generally Linux-based, or in attacks exploiting CSRF flaws, UPnP and SNMP misconfigurations or even a complex drive-by pharming.
Strikingly, not only is this kind of fairly largely ignored by users, but the security community itself pays little attention. It is quite common to see reminders about the importance of installing security patches to the operating system, but few speak of the need to update DSL modem firmware.
Without much fanfare, a vulnerability showing a flaw in a specific modem was revealed in March 2011. That failure allowed remote access to an DSL modem. No one knows exactly when criminals began exploiting it remotely. The flaw allows a Cross Site Request Forgery (CSRF) to be performed in the administration panel of the DSL modem, capturing the password set on the device and allowing the attacker to make changes, usually in the DNS servers.