A new vulnerability has been discovered on Cisco Products:
- Cisco IOS and IOS XE Software Smart Install Remote Code Execution Vulnerability
As per Security advisory:
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
- Causing an indefinite loop on the affected device that triggers a watchdog crash.
This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS or IOS XE Software and have the Smart Install client feature enabled.
Cisco hasn’t released a full list of vulnerable devices, instead they provide an online tool to check if your device is vulnerable: the Cisco IOS Software Checker.
HOW TO PROTECT
Cisco has released software updates for their products. Customers without a service contract should obtain upgrades by contacting the Cisco TAC.
Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.
There are no workarounds that address this vulnerability.
Available remediations are:
- Install CISCO hotfix
- Disable the Smart Install Service https://www.cisco.com/c/en/us/td/docs/switches/lan/smart_install/configuration/guide/smart_install/tasks.html
- Apply an ACL on Smart Install Service https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170214-smi
- Use an external firewall to filter access to the port