![]() Any output of or prompt resulting from the command(s) run will appear on the IBC’s local console (this is only possible in IOS 15.2(2)E and later, and IOS XE 3.6.0E and later)ġ Any file from any file system that can be accessed via the regular copy command on the IOS or IOS XE CLI. Execute high-privilege configuration mode CLI commands on an IBC, including do-exec CLI commands.Load an attacker-supplied IOS image onto the IBC.Substitute the client’s startup-config file with a file that the attacker prepared and force a reload of the IBC after a defined time interval.Copy arbitrary 1 files from the IBC to an attacker-controlled TFTP server.Change the TFTP server address on the IBC.The absence of an authorization or authentication mechanism in the Smart Install protocol between the client and the director can allow a client to process crafted SMI protocol messages as if these messages were from the Smart Install director and perform actions similar to those in the following list: Please see the Talos blog post for further information on this tool.įurther information on the Smart Install feature is available in the Smart Install Configuration Guide. The Cisco Talos group has developed a tool that customers can use to scan for devices that have the Smart Install feature enabled in their environment. No configuration is needed in the client switches. The Smart Install feature is enabled by default on client switches. It can also allocate an IP address and hostname to a client. When a client switch is first installed into the network, the director automatically detects the new switch and identifies the correct Cisco IOS image and the configuration file for downloading. The director provides a single management point for images and configuration of client switches. Only Smart Install client switches are affected by the misuse described in this document. A client switch does not need to be directly connected to the director but can be up to seven hops away. The Smart Install feature incorporates no authentication by design.Ī Smart Install network consists of exactly one Smart Install director switch or router, also known as an integrated branch director (IBD), and one or more Smart Install client switches, also known as integrated branch clients (IBCs). The feature allows a customer to ship a Cisco switch to any location, install it in the network, and power it on without additional configuration requirements. Cisco Coverage for Smart Install Client Protocol AbuseĪdditional Information Cisco Smart InstallĬisco Smart Install is a « plug-and-play » configuration and image-management feature that provides zero-touch deployment for new (typically access layer) switches.Cisco PSIRT – Mitigating and Detecting Potential Abuse of Cisco Smart Install Feature.These blog posts are available at the following links: These issues have been reported by Tenable Network Security, Daniel Turner of Trustwave SpiderLabs, and Alexander Evstigneev and Dmitry Kuznetsov of Digital Security.Ĭisco has recently published blog posts alerting our customers about the need to ensure their network switches are properly protected against abuse of the Smart Install feature, as Cisco has learned of a public posting that details potential abuse of this feature and has received reports of attacks when Smart Install was left enabled. ![]() Customers who are seeking more than zero-touch deployment should consider deploying the Cisco Network Plug and Play solution instead.Ĭisco has updated the Smart Install Configuration Guide to include security best practices regarding the deployment of the Cisco Smart Install feature within customer infrastructures. ![]() Several researchers have reported on the use of Smart Install (SMI) protocol messages toward Smart Install clients, also known as integrated branch clients (IBC), allowing an unauthenticated, remote attacker to change the startup-config file and force a reload of the device, load a new IOS image on the device, and execute high-privilege CLI commands on switches running Cisco IOS and IOS XE Software.Ĭisco does not consider this a vulnerability in Cisco IOS, IOS XE, or the Smart Install feature itself but a misuse of the Smart Install protocol, which does not require authentication by design. Customers who have not done so are encouraged to follow guidance in the Recommendations section of this notice to assess and ensure their network switches are properly protected against abuse of the Smart Install feature. This could leave the involved devices susceptible to misuse of the feature. Cisco is aware of a significant increase in Internet scans attempting to detect devices where, after completing setup, the Smart Install feature remains enabled and without proper security controls.
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