CVE-2018-0171

Name of the Vulnerable Software and Affected Versions Cisco IOS and IOS XE Software (affected versions not specified)

Description A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition, or to execute arbitrary code on an affected device. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted Smart Install message to an affected device on TCP port 4786. A successful exploit could allow the attacker to cause a buffer overflow on the affected device, which could have the following impacts: triggering a reload of the device, allowing the attacker to execute arbitrary code on the device, or causing an indefinite loop on the affected device that triggers a watchdog crash. The vulnerability has been exploited by a Chinese threat actor known as Salt Typhoon to target U.S. telecom networks.

Recommendations To resolve the issue, update the Cisco IOS and IOS XE Software to a version that addresses the vulnerability. As a temporary workaround, consider disabling the Smart Install feature until a patch is available. Restrict access to the TCP port 4786 to minimize the risk of exploitation. Implement a policy of using strong passwords and multi-factor authentication. Disable unnecessary services, including unencrypted web servers and Telnet access. Use SSH for all management protocols and disable the guest console if not required. Regularly update systems, segment networks, and use multi-factor authentication at access points. At the moment, there is no information about a newer version that contains a fix for this vulnerability.