CVE-2021-1591
MEDIUMCisco NX-OS - Unauthenticated Access Control Bypass via EtherChannel Port Subscription
Title source: llmDescription
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
Patch, Vendor Advisory vendor-advisory
x_refsource_cisco
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nexus-acl-vrvQYPVe
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