A vulnerability in IPv6 traffic processing of Cisco IOS XE Wireless Controller Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a Layer 2 (L2) loop in a configured VLAN, resulting in a denial of service (DoS) condition for that VLAN. The vulnerability is due to a logic error when processing specific link-local IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet that would flow inbound through the wired interface of an affected device. A successful exploit could allow the attacker to cause traffic drops in the affected VLAN, thus triggering the DoS condition.
This vulnerability carries a HIGH severity rating with a CVSS v3.1 score of 7.4, indicating it requires adjacent network access with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 9 products from cisco, from cisco, from cisco and 6 others, organizations running these solutions should prioritize assessment and patching.
Reported in 2021, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2021-09-23T03:15:20.180
2025-10-30T21:14:18.060
Analyzed
CVSSv3.1: 7.4 (HIGH)
AV:A/AC:L/Au:N/C:N/I:N/A:P
6.5
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | cisco | ios_xe | - | Yes |
| Operating System | cisco | ios_xe | 3.15.1xbs | Yes |
| Operating System | cisco | ios_xe | 3.15.2xbs | Yes |
| Operating System | cisco | ios_xe | 16.7.1 | Yes |
| Operating System | cisco | ios_xe | 16.7.1a | Yes |
| Operating System | cisco | ios_xe | 16.7.1b | Yes |
| Operating System | cisco | ios_xe | 16.7.2 | Yes |
| Operating System | cisco | ios_xe | 16.7.3 | Yes |
| Operating System | cisco | ios_xe | 16.7.4 | Yes |
| Operating System | cisco | ios_xe | 16.8.1 | Yes |
| Operating System | cisco | ios_xe | 16.8.1a | Yes |
| Operating System | cisco | ios_xe | 16.8.1b | Yes |
| Operating System | cisco | ios_xe | 16.8.1c | Yes |
| Operating System | cisco | ios_xe | 16.8.1d | Yes |
| Operating System | cisco | ios_xe | 16.8.1e | Yes |
| Operating System | cisco | ios_xe | 16.8.1s | Yes |
| Operating System | cisco | ios_xe | 16.8.2 | Yes |
| Operating System | cisco | ios_xe | 16.8.3 | Yes |
| Operating System | cisco | ios_xe | 16.9.1 | Yes |
| Operating System | cisco | ios_xe | 16.9.1a | Yes |
| Operating System | cisco | ios_xe | 16.9.1b | Yes |
| Operating System | cisco | ios_xe | 16.9.1c | Yes |
| Operating System | cisco | ios_xe | 16.9.1d | Yes |
| Operating System | cisco | ios_xe | 16.9.1s | Yes |
| Operating System | cisco | ios_xe | 16.9.2 | Yes |
| Operating System | cisco | ios_xe | 16.9.2a | Yes |
| Operating System | cisco | ios_xe | 16.9.2s | Yes |
| Operating System | cisco | ios_xe | 16.9.3 | Yes |
| Operating System | cisco | ios_xe | 16.9.3a | Yes |
| Operating System | cisco | ios_xe | 16.9.3h | Yes |
| Operating System | cisco | ios_xe | 16.9.3s | Yes |
| Operating System | cisco | ios_xe | 16.9.4 | Yes |
| Operating System | cisco | ios_xe | 16.9.4c | Yes |
| Operating System | cisco | ios_xe | 16.9.5 | Yes |
| Operating System | cisco | ios_xe | 16.9.5f | Yes |
| Operating System | cisco | ios_xe | 16.9.6 | Yes |
| Operating System | cisco | ios_xe | 16.9.7 | Yes |
| Operating System | cisco | ios_xe | 16.10.1 | Yes |
| Operating System | cisco | ios_xe | 16.10.1a | Yes |
| Operating System | cisco | ios_xe | 16.10.1b | Yes |
| Operating System | cisco | ios_xe | 16.10.1c | Yes |
| Operating System | cisco | ios_xe | 16.10.1d | Yes |
| Operating System | cisco | ios_xe | 16.10.1e | Yes |
| Operating System | cisco | ios_xe | 16.10.1f | Yes |
| Operating System | cisco | ios_xe | 16.10.1g | Yes |
| Operating System | cisco | ios_xe | 16.10.1s | Yes |
| Operating System | cisco | ios_xe | 16.10.2 | Yes |
| Operating System | cisco | ios_xe | 16.10.3 | Yes |
| Operating System | cisco | ios_xe | 16.11.1 | Yes |
| Operating System | cisco | ios_xe | 16.11.1a | Yes |
| Operating System | cisco | ios_xe | 16.11.1b | Yes |
| Operating System | cisco | ios_xe | 16.11.1c | Yes |
| Operating System | cisco | ios_xe | 16.11.1s | Yes |
| Operating System | cisco | ios_xe | 16.11.2 | Yes |
| Operating System | cisco | ios_xe | 16.12.1 | Yes |
| Operating System | cisco | ios_xe | 16.12.1a | Yes |
| Operating System | cisco | ios_xe | 16.12.1c | Yes |
| Operating System | cisco | ios_xe | 16.12.1s | Yes |
| Operating System | cisco | ios_xe | 16.12.1t | Yes |
| Operating System | cisco | ios_xe | 16.12.1w | Yes |
| Operating System | cisco | ios_xe | 16.12.1x | Yes |
| Operating System | cisco | ios_xe | 16.12.1y | Yes |
| Operating System | cisco | ios_xe | 16.12.1z | Yes |
| Operating System | cisco | ios_xe | 16.12.1z1 | Yes |
| Operating System | cisco | ios_xe | 16.12.1za | Yes |
| Operating System | cisco | ios_xe | 16.12.2 | Yes |
| Operating System | cisco | ios_xe | 16.12.2a | Yes |
| Operating System | cisco | ios_xe | 16.12.2s | Yes |
| Operating System | cisco | ios_xe | 16.12.2t | Yes |
| Operating System | cisco | ios_xe | 16.12.3 | Yes |
| Operating System | cisco | ios_xe | 16.12.3a | Yes |
| Operating System | cisco | ios_xe | 16.12.3s | Yes |
| Operating System | cisco | ios_xe | 16.12.4 | Yes |
| Operating System | cisco | ios_xe | 16.12.4a | Yes |
| Operating System | cisco | ios_xe | 17.1.1 | Yes |
| Operating System | cisco | ios_xe | 17.1.1a | Yes |
| Operating System | cisco | ios_xe | 17.1.1s | Yes |
| Operating System | cisco | ios_xe | 17.1.1t | Yes |
| Operating System | cisco | ios_xe | 17.1.2 | Yes |
| Operating System | cisco | ios_xe | 17.1.3 | Yes |
| Operating System | cisco | ios_xe | 17.2.1 | Yes |
| Operating System | cisco | ios_xe | 17.2.1a | Yes |
| Operating System | cisco | ios_xe | 17.2.1r | Yes |
| Operating System | cisco | ios_xe | 17.2.1v | Yes |
| Operating System | cisco | ios_xe | 17.2.2 | Yes |
| Operating System | cisco | ios_xe | 17.2.3 | Yes |
| Operating System | cisco | ios_xe | 17.3.1 | Yes |
| Operating System | cisco | ios_xe | 17.3.1a | Yes |
| Operating System | cisco | ios_xe | 17.3.1w | Yes |
| Operating System | cisco | ios_xe | 17.3.1x | Yes |
| Operating System | cisco | ios_xe | 17.3.1z | Yes |
| Operating System | cisco | ios_xe | 17.3.2 | Yes |
| Operating System | cisco | ios_xe | 17.3.2a | Yes |
| Hardware | cisco | catalyst_9800 | - | No |
| Hardware | cisco | catalyst_9800-40 | - | No |
| Hardware | cisco | catalyst_9800-80 | - | No |
| Hardware | cisco | catalyst_9800-cl | - | No |
| Hardware | cisco | catalyst_9800-l | - | No |
| Hardware | cisco | catalyst_9800-l-c | - | No |
| Hardware | cisco | catalyst_9800-l-f | - | No |
| Hardware | cisco | catalyst_9800_embedded_wireless_controller | - | No |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For cisco's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.