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Case File

CVE-2021-34767

HIGH · CVSS 7.4 EPSS 0.78% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-09-23 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 7.4. It affects Cisco. Public exploit code or proof-of-concept references have been detected in its references. It may lead to a denial-of-service condition.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-34767
Severity
HIGH
CVSS
7.4
EPSS
0.78%
Cisco

Original NVD 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.

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