CVE-2021-1389: Cisco IOS XR and Cisco NX-OS Software IPv6 Access Control List Bypass Vulnerability
A vulnerability in the IPv6 traffic processing of Cisco IOS XR Software and Cisco NX-OS Software for certain Cisco devices could allow an unauthenticated, remote attacker to bypass an IPv6 access control list (ACL) that is configured for an interface of an affected device. The vulnerability is due to improper processing of IPv6 traffic that is sent through an affected device. An attacker could exploit this vulnerability by sending crafted IPv6 packets that traverse the affected device. A successful exploit could allow the attacker to access resources that would typically be protected by the interface ACL.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2021-1389?
CVE-2021-1389 is a vulnerability in the IPv6 traffic processing of Cisco IOS XR Software and Cisco NX-OS Software for certain Cisco devices.
How does CVE-2021-1389 affect Cisco devices?
CVE-2021-1389 allows an unauthenticated, remote attacker to bypass an IPv6 access control list (ACL) configured for an interface on the affected device.
What is the severity of CVE-2021-1389?
CVE-2021-1389 has a severity rating of 6.5 (medium).
Which Cisco devices are affected by CVE-2021-1389?
Cisco IOS XR Software versions 6.6.3, 7.1.0, and 7.2.0, as well as Cisco NX-OS Software, are affected by CVE-2021-1389.
How can I fix CVE-2021-1389?
To fix CVE-2021-1389, it is recommended to upgrade to a fixed software release provided by Cisco.