CVE-2018-0156: Technical Deep-Dive (Auto Refreshed)

Generated on 2026-03-31T21:11:13.344Z. This file is automatically regenerated every 30 minutes by the CVE AI enrichment job using web sources (NVD, MITRE, CISA KEV, GitHub).

Executive Technical Summary

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.

• Context preserved from previous revision: 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. Notes: Ostorlab KEV: One-command to detect most remotely known exploitable vulnerabilities. Sourced from CISA KEV, Google's Tsunami, Ostorlab's Asteroid and Bug Bounty programs.

Technical Details

• CVE: CVE-2018-0156
• KEV date added: 2022-03-03
• KEV due date: 2022-03-17
• NVD published: 2018-03-29
• NVD modified: 2026-01-14
• MITRE modified: 2026-01-12
• CVSS base score: 7.5
• CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
• CVSS exploitability score: 3.9
• CVSS impact score: 3.6
• Attack vector: Network
• Attack complexity: Low
• Privileges required: None
• User interaction: None
• Scope: Unchanged
• Confidentiality impact: None
• Integrity impact: None
• Availability impact: High

Versions and Products Impacted

• cisco / ios (versions: 15.2(2)e4)
• cisco / ios (versions: 15.2(2a)ja)
• cisco / ios xe (versions: 15.2(2)e4)
• cisco / ios xe (versions: 15.2(2a)ja)
• n/a / Cisco IOS and IOS XE (versions: Cisco IOS and IOS XE)

Weakness Classification

• CWE-399
• CWE-20

Repositories for Lab Validation (Public Examples)

• Ostorlab/KEV | stars: 608 | updated: 2026-03-23 | https://github.com/Ostorlab/KEV
  Notes: Ostorlab KEV: One-command to detect most remotely known exploitable vulnerabilities. Sourced from CISA KEV, Google's Tsunami, Ostorlab's Asteroid and Bug Bounty programs.
• kaungsithu19/Black-Box-Pen-testing-DVWA | stars: 0 | updated: 2025-08-28 | https://github.com/kaungsithu19/Black-Box-Pen-testing-DVWA
  Notes: Black-box penetration test on Damn Vulnerable Web Application (DVWA 1.0.7) using Kali Linux. Includes reconnaissance, exploitation of CVEs, privilege escalation, and remediation strategies with detailed report and exploit walkthroughs.

People and Organizations Mentioned

• cisco
• IOS Software and Cisco IOS XE Software
• Ostorlab
• kaungsithu19

Practical Defensive Validation (Authorized Only)

1. Use only isolated environments and systems you own or are explicitly authorized to test.
2. Snapshot infrastructure before validation and preserve baseline logs (EDR, SIEM, OS, app).
3. Inventory cisco / ios (versions: 15.2(2)e4) assets and confirm exact vulnerable versions with automated checks.
4. Patch in staged environments and validate closure with scanners + service health checks.
5. Map detections to MITRE ATT&CK tactics relevant to your environment and tune alert quality.

References

• NVD record: https://nvd.nist.gov/vuln/detail/CVE-2018-0156
• MITRE CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0156
• CISA KEV Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• CISA KEV JSON feed: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
• KEV notes: https://nvd.nist.gov/vuln/detail/CVE-2018-0156
• 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
• Repository example: https://github.com/Ostorlab/KEV
• Repository example: https://github.com/kaungsithu19/Black-Box-Pen-testing-DVWA

This content is for defensive security training and authorized validation only.