VULNERABILITY INTELLIGENCE

CVE-2021-34767

CVSS score7.4 HIGH
EPSS probability0.78%
CISA KEVNot currently listed
Published2021-09-23
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

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.

Weakness classification

  • psirt@cisco.com: CWE-670
  • nvd@nist.gov: CWE-670

Primary references