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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2021-34767 Detail

Description

A vulnerability in IPv6 traffic processing of Cisco IOS XE Wireless Controller Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a Layer 2 (L2) loop in a configured VLAN, resulting in a denial of service (DoS) condition for that VLAN. The vulnerability is due to a logic error when processing specific link-local IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet that would flow inbound through the wired interface of an affected device. A successful exploit could allow the attacker to cause traffic drops in the affected VLAN, thus triggering the DoS condition.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-ipv6-dos-NMYeCnZv CVE, Cisco Systems, Inc. Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-670 Always-Incorrect Control Flow Implementation cwe source acceptance level NIST   Cisco Systems, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

5 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-34767
NVD Published Date:
09/22/2021
NVD Last Modified:
10/30/2025
Source:
Cisco Systems, Inc.