CVE-2021-1591

MEDIUM

Cisco NX-OS - Unauthenticated Access Control Bypass via EtherChannel Port Subscription

Title source: llm
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 5.8
EPSS 0.0029
EPSS Percentile 52.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-284
Status published
Products (1)
cisco/nx-os 9.3\(4\)
Published Aug 25, 2021
Tracked Since Feb 18, 2026