MEDIUM · 4.7

CVE-2025-20137

A vulnerability in the access control list (ACL) programming of Cisco IOS Software that is running on Cisco Catalyst 1000 Switches and Cisco Catalyst 2960L Switches could allow an unauthenticated, rem...

Vulnerability Description

A vulnerability in the access control list (ACL) programming of Cisco IOS Software that is running on Cisco Catalyst 1000 Switches and Cisco Catalyst 2960L Switches could allow an unauthenticated, remote attacker to bypass a configured ACL. This vulnerability is due to the use of both an IPv4 ACL and a dynamic ACL of IP Source Guard on the same interface, which is an unsupported configuration. An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass an ACL on the affected device. Note: Cisco documentation has been updated to reflect that this is an unsupported configuration. However, Cisco is publishing this advisory because the device will not prevent an administrator from configuring both features on the same interface. There are no plans to implement the ability to configure both features on the same interface on Cisco Catalyst 1000 or Catalyst 2960L Switches.

CVSS Score

4.7

MEDIUM

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Attack Vector
ADJACENT_NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE

Affected Products

VendorProductVersions
CiscoIos15.2\(5a\)e
CiscoCatalyst 1000-16Fp-2G-L-
CiscoCatalyst 1000-16P-2G-L-
CiscoCatalyst 1000-16T-2G-L-
CiscoCatalyst 1000-16T-E-2G-L-
CiscoCatalyst 1000-24Fp-4G-L-
CiscoCatalyst 1000-24Fp-4X-L-
CiscoCatalyst 1000-24P-4G-L-
CiscoCatalyst 1000-24P-4X-L-
CiscoCatalyst 1000-24Pp-4G-L-
CiscoCatalyst 1000-24T-4G-L-
CiscoCatalyst 1000-24T-4X-L-
CiscoCatalyst 1000-48Fp-4G-L-
CiscoCatalyst 1000-48Fp-4X-L-
CiscoCatalyst 1000-48P-4G-L-
CiscoCatalyst 1000-48P-4X-L-
CiscoCatalyst 1000-48Pp-4G-L-
CiscoCatalyst 1000-48T-4G-L-
CiscoCatalyst 1000-48T-4X-L-
CiscoCatalyst 1000-8Fp-2G-L-

Related Weaknesses (CWE)

References

FAQ

What is CVE-2025-20137?

CVE-2025-20137 is a vulnerability with a CVSS score of 4.7 (MEDIUM). A vulnerability in the access control list (ACL) programming of Cisco IOS Software that is running on Cisco Catalyst 1000 Switches and Cisco Catalyst 2960L Switches could allow an unauthenticated, rem...

How severe is CVE-2025-20137?

CVE-2025-20137 has been rated MEDIUM with a CVSS base score of 4.7/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-20137?

Check the references section above for vendor advisories and patch information. Affected products include: Cisco Ios, Cisco Catalyst 1000-16Fp-2G-L, Cisco Catalyst 1000-16P-2G-L, Cisco Catalyst 1000-16T-2G-L, Cisco Catalyst 1000-16T-E-2G-L.