National Cyber Awareness System: 07/26/2013 04:08 PM EDT
Original release date: July 26, 2013 | Last revised: October 03, 2013
Systems AffectedAny system connected to the internet running the Intelligent Platform Management Interface (IPMI) may be affected. IPMI is resident on many server platforms, and provides low-level access to a system that can override operating system controls. OverviewAttackers can easily identify and access systems that run IPMI and are connected to the Internet. It is important to restrict IPMI access to specific management IP addresses within an organization and preferably separated into a separate LAN segment. DescriptionWhat is the Intelligent Platform Management Interface (IPMI)? IPMI is a low level interface specification that has been adopted by many hardware vendors. It allows a system administrator to remotely manage servers at the hardware level. IPMI runs on the Baseboard Management Controller (BMC) and provides access to the BIOS, disks, and other hardware. It also supports remote booting from a CD or through the network, and monitoring of the server environment. The BMC itself also runs a limited set of network services to facilitate management and communications amongst systems. What Is the Risk? Attackers can use IPMI to essentially gain physical-level access to the server. An attacker can reboot the system, install a new operating system, or compromise data, bypassing any operating system controls. Some issues identified by Dan Farmer:
Attackers can easily search and identify internet-connected target systems, and IPMI is no exception. ImpactAn attacker with knowledge of IPMI can search for, and find, open management interfaces. Many of these interfaces utilize default or no passwords, or weak encryption. Further consequences depend on the type and use of the compromised system. At the very least, an attacker can compromise confidentiality, integrity, and availability of the server once gaining access to the BMC. SolutionRestrict IPMI to Internal Networks Restrict IPMI traffic to trusted internal networks. Traffic from IPMI (usually UDP port 623) should be restricted to a management VLAN segment with strong network controls. Scan for IPMI usage outside of the trusted network and monitor the trusted network for abnormal activity. Utilize Strong Passwords Devices running IPMI should have strong, unique passwords set for the IPMI service. See US-CERT Security Tip ST04-002 and Password Security, Protection, and Management for more information on password security. Encrypt Traffic Enable encryption on IPMI interfaces, if possible. Check your manufacturer manual for details on how to set up encryption. Require Authentication "cipher 0" is an option enabled by default on many IPMI enabled devices that allows authentication to be bypassed. Disable "cipher 0" to prevent attackers from bypassing authentication and sending arbitrary IPMI commands. Anonymous logins should also be disabled. Sanitize Flash Memory at End of Life Follow manufacturer recommendations for sanitizing passwords. If none exists, destroy the flash chip, motherboard, or other areas the IPMI password may be stored. Identify Affected Products
Vendor Information Dell has provided the following information related to this Technical Alert: References
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