Assessment
Why it matters
CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 99.5%; technical severity is CVSS 9.8.
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. Cisco Bug IDs: CSCvg76186.
Who should care
- Teams operating IOS, IOS and IOS XE
- Vulnerability and exposure management teams
- Security operations teams monitoring exploitation activity
Response plan
What I would do
- Confirm whether IOS, IOS and IOS XE is present in the environment.
- Identify affected versions and establish whether vulnerable services are exposed or reachable.
- Apply updates per vendor instructions.
- Review relevant security telemetry for evidence of attempted or successful exploitation.
- Document the remediation decision and track it to verified completion.
Vendor remediation
Patch and remediation links
Use the vendor source below to confirm the correct fixed version, package or mitigation for your affected product.
Technical details
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-20
- Affected versions
- Cisco IOS (Version: 15.2(5)e); Cisco IOS and IOS XE
- Published
- 28 March 2018
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
Signal timeline
- CVE published
- Added to CISA KEV
- Latest EPSS score: 99.5%
- Signal calculated at 85
External references
- Government advisory from www.cisa.gov
- Third-party advisory from www.securityfocus.com
- Third-party advisory from www.securitytracker.com
- Government advisory from ics-cert.us-cert.gov
- Government advisory from ics-cert.us-cert.gov
- Vendor advisory from tools.cisco.com
- Technical reference from www.darkreading.com