CVE-2017-12238: Technical Deep-Dive (Auto Refreshed)

Generated on 2026-04-02T23:31:19.200Z. 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 Virtual Private LAN Service (VPLS) code of Cisco IOS 15.0 through 15.4 for Cisco Catalyst 6800 Series Switches could allow an unauthenticated, adjacent attacker to cause a C6800-16P10G or C6800-16P10G-XL type line card to crash, resulting in a denial of service (DoS) condition. The vulnerability is due to a memory management issue in the affected software. An attacker could exploit this vulnerability by creating a large number of VPLS-generated MAC entries in the MAC address table of an affected device. A successful exploit could allow the attacker to cause a C6800-16P10G or C6800-16P10G-XL type line card to crash, resulting in a DoS condition. This vulnerability affects Cisco Catalyst 6800 Series Switches that are running a vulnerable release of Cisco IOS Software and have a Cisco C6800-16P10G or C6800-16P10G-XL line card in use with Supervisor Engine 6T. To be vulnerable, the device must also be configured with VPLS and the C6800-16P10G or C6800-16P10G-XL line card needs to be the core-facing MPLS interfaces. Cisco Bug IDs: CSCva61927.

• Context preserved from previous revision: A vulnerability in the Virtual Private LAN Service (VPLS) code of Cisco IOS 15.0 through 15.4 for Cisco Catalyst 6800 Series Switches could allow an unauthenticated, adjacent attacker to cause a C6800-16P10G or C6800-16P10G-XL type line card to crash, resulting in a denial of service (DoS) condition. The vulnerability is due to a memory management issue in the affected software. An attacker could exploit this vulnerability by creating a large number of VPLS-generated MAC entries in the MAC address table of an affected device. A successful exploit could allow the attacker to cause a C6800-16P10G or C6800-16P10G-XL type line card to crash, resulting in a DoS condition. This vulnerability affects Cisco Catalyst 6800 Series Switches that are running a vulnerable release of Cisco IOS Software and have a Cisco C6800-16P10G or C6800-16P10G-XL line card in use with Supervisor Engine 6T. To be vulnerable, the device must also be configured with VPLS and the C6800-16P10G or C6800-16P10G-XL line card needs to be the core-facing MPLS interfaces. Cisco Bug IDs: CSCva61927. 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-2017-12238
• KEV date added: 2022-03-03
• KEV due date: 2022-03-24
• NVD published: 2017-09-29
• NVD modified: 2026-01-13
• MITRE modified: 2026-01-12
• CVSS base score: 6.5
• CVSS vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
• CVSS exploitability score: 2.8
• CVSS impact score: 3.6
• Attack vector: Adjacent
• 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: >= 15.0, <= 15.4)
• n/a / Cisco IOS (versions: Cisco IOS)

Weakness Classification

• CWE-399
• NVD-CWE-noinfo

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.

People and Organizations Mentioned

• cisco
• Catalyst 6800 Series Switches
• Ostorlab

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: >= 15.0, <= 15.4) 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-2017-12238
• MITRE CVE record: https://www.cve.org/CVERecord?id=CVE-2017-12238
• 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-2017-12238
• http://www.securityfocus.com/bid/101040
• http://www.securitytracker.com/id/1039453
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-vpls
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12238
• Repository example: https://github.com/Ostorlab/KEV

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