CVE-2018-0171

Cisco IOS and IOS XE Software Smart Install Remote Code Execution Vulnerability

IN CISA KEV

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.

Vendor: Cisco
Product: IOS and IOS XE
CVSS 3.1: 9.8 (critical), scored by NVD (primary)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 3.1: 7.5 (high), scored by 134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-20, CWE-787
Published: 2018-03-28
NVD modified: 2026-06-17
NVD status: Analyzed

CISA KEV

Date added: 2021-11-03
Due date: 2022-05-03
Ransomware use: Unknown
Required action: Apply updates per vendor instructions.

EPSS

99.5% chance of exploitation in the next 30 days (percentile 99th)

FIRST EPSS, updated 17 Oct 2026. About EPSS

CVSS is severity, EPSS is likelihood, KEV means already exploited. EPSS is a statistical probability, not a certainty: a low score does not make a bug safe, and a high one does not prove it is being exploited.

References

www.securityfocus.com (Third Party Advisory, VDB Entry)
www.securitytracker.com (Third Party Advisory, VDB Entry)
ics-cert.us-cert.gov (Third Party Advisory, US Government Resource)
ics-cert.us-cert.gov (Third Party Advisory, US Government Resource)
tools.cisco.com (Vendor Advisory)
www.darkreading.com (Press/Media Coverage)
www.securityfocus.com (Third Party Advisory, VDB Entry)
www.securitytracker.com (Third Party Advisory, VDB Entry)
ics-cert.us-cert.gov (Third Party Advisory, US Government Resource)
ics-cert.us-cert.gov (Third Party Advisory, US Government Resource)
tools.cisco.com (Vendor Advisory)
www.darkreading.com (Press/Media Coverage)

Data last updated 18 Oct 2026. Sources: NVD API 2.0, CISA KEV catalog, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.