CVE-2021-1591

Cisco Nexus 9500 Series Switches Access Control List Bypass Vulnerability

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.

Category

5.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory cisco.com
Affected: Cisco Cisco NX-OS Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nexus-acl-vrvQYPVe patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-1591?
CVE-2021-1591 has been scored as a medium severity vulnerability.
How to fix CVE-2021-1591?
To fix CVE-2021-1591, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-1591 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1591 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1591?
CVE-2021-1591 affects Cisco Cisco NX-OS Software.
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