CVE-2021-1389: 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…

PriorityP339medium6.5CVSS 3.1

AVNACLPRNUINSUCLILAN

EPSS

1.22%

65.6th percentile

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

5 ranges

Vendor	Product	Version range	Fixed in
cisco	cisco_ios_xr_software	—	—
cisco	ios_xr	< 6.6.3	6.6.3
cisco	ios_xr	—	—
cisco	ios_xr	—	—
cisco	ios_xr_and_cisco_nx-os	—	—

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

nvdv2.06.4MEDIUMAV:N/AC:L/Au:N/C:P/I:P/A:N

vendor_cisco5.8MEDIUM

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