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    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, 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.

    Published:Feb 4, 2021
    Last Modified:Nov 21, 2024
    EPS:Feb 4, 2021
    EPSS Score:0.00226
    CVSS Score:5.8

    Affected Products

    Vendor
    Cisco
    Product
    Ios Xr
    Vendor
    Cisco
    Product
    Ncs 540
    Vendor
    Cisco
    Product
    Ncs 5501
    Vendor
    Cisco
    Product
    Ncs 5501-se
    Vendor
    Cisco
    Product
    Ncs 5502
    Vendor
    Cisco
    Product
    Ncs 5502-se
    Vendor
    Cisco
    Product
    Ncs 5508
    Vendor
    Cisco
    Product
    Ncs 5516
    Vendor
    Cisco
    Product
    Ncs 560
    Vendor
    Cisco
    Product
    Nexus 3600
    Vendor
    Cisco
    Product
    Nexus 9500 R
    Vendor
    Cisco
    Product
    Nx-os

    Exploits

    No exploit reference

    Common Weakness Enumeration

    CWE-284 Improper Access Control

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    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High