CVE-2018-0171: Cisco IOS and IOS XE Software Smart Install Remote Code Execution Vulnerability

CISA Known Exploited Vulnerabilities

Name

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

Vendor

Cisco

Product

IOS and IOS XE

Added to the catalog

2021-11-03

Due date for US federal agencies

2022-05-03

Weaknesses

CWE-20

Catalog version

2026.10.30

Cisco IOS and IOS XE Software improperly validates packet data, allowing an unauthenticated, remote attacker to trigger a reload of an affected device, cause a denial-of-service (DoS) condition, or perform code execution on the affected device.

Required action (CISA)

Apply updates per vendor instructions.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

• https://nvd.nist.gov/vuln/detail/CVE-2018-0171

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2018-03-28T22:29:01.063

Last modified

2026-06-17T01:29:59.627

Weaknesses

CWE-20, CWE-787

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.

References

• http://www.securityfocus.com/bid/103538 (Third Party Advisory, VDB Entry)
• http://www.securitytracker.com/id/1040580 (Third Party Advisory, VDB Entry)
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04 (Third Party Advisory, US Government Resource)
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05 (Third Party Advisory, US Government Resource)
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi2 (Vendor Advisory)
• https://www.darkreading.com/perimeter/attackers-exploit-cisco-switch-issue-as-vendor-warns-of-yet-another-critical-flaw/d/d-id/1331490 (Press/Media Coverage)
• http://www.securityfocus.com/bid/103538 (Third Party Advisory, VDB Entry)
• http://www.securitytracker.com/id/1040580 (Third Party Advisory, VDB Entry)
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04 (Third Party Advisory, US Government Resource)
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05 (Third Party Advisory, US Government Resource)
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi2 (Vendor Advisory)
• https://www.darkreading.com/perimeter/attackers-exploit-cisco-switch-issue-as-vendor-warns-of-yet-another-critical-flaw/d/d-id/1331490 (Press/Media Coverage)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0171 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:41:35.381Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2018-0171

CVE record

Assigner

cisco

State

PUBLISHED

Published

2018-03-28T22:00:00.000Z

Updated

2026-01-12T21:34:43.255Z

Problem types

CWE-20

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.

References

• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04
• 1040580
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi2
• https://www.darkreading.com/perimeter/attackers-exploit-cisco-switch-issue-as-vendor-warns-of-yet-another-critical-flaw/d/d-id/1331490
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05
• 103538

Read on 2026-11-03T00:35:59.490Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2018/0xxx/CVE-2018-0171.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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