CVE-2025-20316
MEDIUM EPSS 21.1%
Published Sep 24, 20259mo ago · Modified Jun 17, 20262w ago
5.3 CVSS 3.1
Published Sep 24, 2025 9mo ago
Last Modified Jun 17, 2026 2w ago
Description
A vulnerability in the access control list (ACL) programming of Cisco IOS XE Software for Cisco Catalyst 9500X and 9600X Series Switches could allow an unauthenticated, remote attacker to bypass a configured ACL on an affected device. This vulnerability is due to the flooding of traffic from an unlearned MAC address on a switch virtual interface (SVI) that has an egress ACL applied. An attacker could exploit this vulnerability by causing the VLAN to flush its MAC address table. This condition can also occur if the MAC address table is full. A successful exploit could allow the attacker to bypass an egress ACL on an affected device.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity Low
Availability None
Threat Intelligence
EPSS Exploit Probability
21.1% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-284
References 1
- sec.cloudapps.cisco.com https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cat9k-acl-L4K7VXgD
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.