CVE-2018-0156

Name: CVE-2018-0156
Creator: NVD / NIST
Published: 2018-03-28T22:29:00.467+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10Actively ExploitedEPSS 8.37%

Last modified Jun 17, 2026

CVE-2018-0156 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. The vulnerability is due to improper validation of packet data. CISA has confirmed active exploitation in the wild. EPSS estimates a 8.37% chance of exploitation in the next 30 days.

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. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted packet to an affected device on TCP port 4786. Only Smart Install client switches are affected. Cisco devices that are configured as a Smart Install director are not affected by this vulnerability. Cisco Bug IDs: CSCvd40673.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

8.37%

94.3th percentile

Probability of exploitation in the next 30 days. Learn more

Exploitation Status

This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by Mar 17, 2022.

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Ios	15.2\(2\)e4
Cisco	Ios	15.2\(2a\)ja
Cisco	Ios Xe	15.2\(2\)e4
Cisco	Ios Xe	15.2\(2a\)ja

References

http://www.securityfocus.com/bid/103569Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040596Third Party Advisory, VDB Entry
https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04Third Party Advisory, US Government Resource
https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05Third Party Advisory, US Government Resource
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smiVendor Advisory
http://www.securityfocus.com/bid/103569Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040596Third Party Advisory, VDB Entry
https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04Third Party Advisory, US Government Resource
https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05Third Party Advisory, US Government Resource
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smiVendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0156US Government Resource

Timeline

Published: Mar 28, 2018
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2018-0156?

How severe is CVE-2018-0156?

CVE-2018-0156 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 8.37% probability of exploitation in the next 30 days. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.

How do I fix CVE-2018-0156?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-0156?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST