A network security audit should be near the top of IT managers list of things to do since Tuesdays disclosure of the existence of a test tool that, when used maliciously, can overcome SNMPv1 (Simple Network Management Protocol, version 1) in a wide variety of caching devices, routers, switches, printers and a myriad of other infrastructure devices.
Instead of making the security audit the first step in a remediation plan, eWEEK Labs recommends that IT managers take this occasion to put together a plan that enables ongoing management of the wide range of devices that are threatened.
A security audit is a good opportunity to manage devices with both short-term and long-term perspectives to reduce IT costs and improve business processes. The short-term response to the current threat is to apply the specific patch for SNMP 1. For the long term, IT departments should systematically upgrade their operating systems.
Over the past several months, eWEEK Labs has advocated simplifying networks, systems and applications to improve security. In this case, SNMP commonly uses TCP ports 161 and 162, 191 (both TCP and UDP) along with three or four others. A good fix is to use a port scan tool to see if these ports are open. Next determine if the processes supported by these ports are needed. If yes, leave them open, but monitor their use. If no, consider turning them off.
This is a great example of a short-term solution. Combined with a quick check of the equipment vendors Web site for a patch to the SNMP code, managers should be able to make the equipment as good as gold.
Now repeat for 3,000 or 4,000 devices.
This is where the long-term management strategy must equipment and determining operating system versions is essential for this type of project in order to reduce IT operational costs.
In the case of the SNMP attack, eWEEK Labs advises that IT managers take the time to do the project right. Although reports show that the tool, designed by the Oulu University Secure Programming Group, is likely circulating underground, many SNMP-equipped devices are obsolete and are no longer supported by their manufacturers. Thus, a plan that combines shielding the network from SNMP probes while locating affected devices and installing updated software images is both urgent and massive. Putting plans in place to track and update software versions on these devices—not just fixing the current problem—is an essential step for IT to proactively strengthen network security.
