Improper access control in Cisco Systems, Inc products - CVE-2025-20316
Published: September 25, 2025
Vulnerability identifier: #VU116117
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2025-20316
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Cisco Systems, Inc
Affected software:
Catalyst 9500X Series Switches
Catalyst 9600X Series Switches
Cisco IOS XE
Catalyst 9500X Series Switches
Catalyst 9600X Series Switches
Cisco IOS XE
Detailed vulnerability description
The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to the flooding of traffic from an unlearned MAC address on a switch virtual interface (SVI) that has an egress ACL applied. A remote attacker can bypass an egress ACL on the target device.
How to mitigate CVE-2025-20316
Install updates from vendor's website.