What’s Vulnerable › Vulnerabilities

CVE-2018-0156: Cisco IOS Software and Cisco IOS XE Software Smart Install Denial-of-Service Vulnerability

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: yes — in CISA KEV since 2022-03-03
• EPSS: 9.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-03-28 · updated 2026-06-17
• Weakness: CWE-399

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.

Affected products

• Cisco IOS: 15.2(2)e4, 15.2(2a)ja
• Cisco IOS XE: 15.2(2)e4, 15.2(2a)ja

References

• http://www.securityfocus.com/bid/103569
• http://www.securitytracker.com/id/1040596
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi
• http://www.securityfocus.com/bid/103569
• http://www.securitytracker.com/id/1040596
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04
• https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0156

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