CVE-2021-1591

MediumCVSS 5.3/10Last modified Jun 17, 2026

Description

A vulnerability in the EtherChannel port subscription logic of Cisco Nexus 9500 Series Switches could allow an unauthenticated, remote attacker to bypass access control list (ACL) rules that are configured on an affected device. This vulnerability is due to oversubscription of resources that occurs when applying ACLs to port channel interfaces. An attacker could exploit this vulnerability by attempting to access network resources that are protected by the ACL. A successful exploit could allow the attacker to access network resources that would be protected by the ACL that was applied on the port channel interface.

Metrics

CVSS 3.1 5.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Aug 25, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-1591: Medium severity, CVSS 5.3 | Vulnix