Cisco · Catalyst 6800 Series Switches
CVE-2017-12238
Cisco Catalyst 6800 Series Switches VPLS Denial-of-Service Vulnerability
What it is
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.
CISA: A vulnerability in the Virtual Private LAN Service (VPLS) code of Cisco IOS for Cisco Catalyst 6800 Series Switches could allow an unauthenticated, adjacent attacker to cause a denial of service.
What to do
Apply updates per vendor instructions.
Deadline for US federal agencies: March 24, 2022
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|---|---|---|---|---|
| Oct 14, 2026 | Relative Path Traversal | Secure Email Gateway | Critical 9.8 | 2.2% |
| Sep 30, 2026 | Hex Encoding | Catalyst SD-WAN Manager | Critical 9.8 | 39% |
| Sep 16, 2026 | Incorrect Use of Privileged APIs | Identity Services Engine | Critical 10.0 | 76% |
| Sep 14, 2026 | SQL Injection | Secure Email Gateway | Critical 9.8 | 30% |
| Sep 9, 2026 | Firewall Management Center Authentication Bypass Using an Alternate Path or Channel | Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management | Critical 10.0 | 88% |
| Aug 11, 2026 | Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection | Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) | High 8.6 | 1.0% |
| Jul 29, 2026 | Secure Firewall Management Center Use of Hard-coded Password | Secure Firewall Management Center (FMC) | Medium 5.3 | 35% |
| Jul 13, 2026 | Cross-Site Request Forgery | IOS | High 8.1 | 34% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.