A vulnerability in the dynamic access control list (ACL) feature of Cisco IOS XE Software running on Cisco Catalyst 4000 Series Switches could allow an unauthenticated, adjacent attacker to cause dynamic ACL assignment to fail and the port to fail open. This could allow the attacker to pass traffic to the default VLAN of the affected port. The vulnerability is due to an uncaught error condition that may occur during the reassignment of the auth-default-ACL dynamic ACL to a switch port after 802.1x authentication fails. A successful exploit of this issue could allow a physically adjacent attacker to bypass 802.1x authentication and cause the affected port to fail open, allowing the attacker to pass traffic to the default VLAN of the affected switch port. Cisco Bug IDs: CSCvc72751.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.3, indicating it requires adjacent network access with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited integrity, for affected systems. Impacting 2 products from cisco, from cisco organizations running these solutions should prioritize assessment and patching.
First disclosed in 2017, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.
2017-09-07T21:29:00.317
2025-04-20T01:37:25.860
Deferred
CVSSv3.0: 4.3 (MEDIUM)
AV:A/AC:L/Au:N/C:N/I:P/A:N
6.5
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | cisco | ios_xe | - | Yes |
| Hardware | cisco | catalyst_4000 | - | 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.