CVE-2021-1228

Cisco Nexus 9000 Series Fabric Switches ACI Mode Fabric Infrastructure VLAN Unauthorized Access Vulnerability

Description

A vulnerability in the fabric infrastructure VLAN connection establishment of Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, adjacent attacker to bypass security validations and connect an unauthorized server to the infrastructure VLAN. This vulnerability is due to insufficient security requirements during the Link Layer Discovery Protocol (LLDP) setup phase of the infrastructure VLAN. An attacker could exploit this vulnerability by sending a crafted LLDP packet on the adjacent subnet to an affected device. A successful exploit could allow the attacker to connect an unauthorized server to the infrastructure VLAN, which is highly privileged. With a connection to the infrastructure VLAN, the attacker can make unauthorized connections to Cisco Application Policy Infrastructure Controller (APIC) services or join other host endpoints.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.06%
Vendor Advisory cisco.com
Affected: Cisco Cisco NX-OS System Software in ACI Mode 11.0(1b)
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-unauth-access-5PWzDx2w vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-1228?
CVE-2021-1228 has been scored as a high severity vulnerability.
How to fix CVE-2021-1228?
To fix CVE-2021-1228, 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-2021-1228 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1228 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-2021-1228?
CVE-2021-1228 affects Cisco Cisco NX-OS System Software in ACI Mode 11.0(1b).
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