6.5
MEDIUM
CVE-2021-1389
Cisco IPv6 ACL Bypass Vulnerability
Description

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.

INFO

Published Date :

Feb. 4, 2021, 5:15 p.m.

Last Modified :

Nov. 21, 2024, 5:44 a.m.

Remotely Exploitable :

Yes !

Impact Score :

2.5

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-1389 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Cisco nx-os
2 Cisco ios_xr
3 Cisco nexus_3600
4 Cisco ncs_5501-se
5 Cisco ncs_5502-se
6 Cisco ncs_5508
7 Cisco ncs_5516
8 Cisco ncs_540
9 Cisco ncs_5501
10 Cisco ncs_5502
11 Cisco ncs_560
12 Cisco nexus_9500_r
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-1389.

URL Resource
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-1389 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-1389 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Removed CVSS V3 Cisco Systems, Inc. AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
    Added CVSS V3.1 Cisco Systems, Inc. AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
  • Reanalysis by [email protected]

    Sep. 20, 2022

    Action Type Old Value New Value
    Added CWE NIST NVD-CWE-Other
  • Initial Analysis by [email protected]

    Feb. 08, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:N)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
    Changed Reference Type https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j No Types Assigned https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j Vendor Advisory
    Added CPE Configuration AND OR *cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* versions up to (excluding) 6.6.3 *cpe:2.3:o:cisco:ios_xr:7.1.0:*:*:*:*:*:*:* *cpe:2.3:o:cisco:ios_xr:7.2.0:*:*:*:*:*:*:* OR cpe:2.3:h:cisco:ncs_540:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5501:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5501-se:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5502:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5502-se:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5508:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5516:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_560:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:cisco:nx-os:-:*:*:*:*:*:*:* OR cpe:2.3:h:cisco:nexus_3600:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:nexus_9500_r:-:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Feb. 04, 2021

    Action Type Old Value New Value
    Changed Description 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. 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.
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-1389 is associated with the following CWEs:

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.13 }} 0.02%

score

0.47301

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability