CVE-2021-1621

A vulnerability in the Layer 2 punt code of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a queue wedge on an interface that receives specific Layer 2 frames, resulting in a denial of service (DoS) condition. This vulnerability is due to improper handling of certain Layer 2 frames. An attacker could exploit this vulnerability by sending specific Layer 2 frames on the segment the router is connected to. A successful exploit could allow the attacker to cause a queue wedge on the interface, resulting in a DoS condition.

• CWE-399

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-quewedge-69BsHUBWPatch, Vendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-quewedge-69BsHUBWPatch, Vendor Advisory

Published

Sep 23, 2021

Last Modified

Jun 17, 2026

Status

Modified

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