Rewterz Threat Advisory – CVE-2021-34767 – Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers

Severity

High

Analysis Summary

CVE-2021-34767

Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers is vulnerable to a denial of service, caused by a logic error when processing specific link-local IPv6 traffic. By sending a specially-crafted IPv6 packet, a remote attacker could exploit this vulnerability to cause traffic drops in the affected VLAN.

Impact

Denial of Service

Affected Vendors

Cisco

Affected Products

Cisco IOS XE Software
Cisco Catalyst 9800 Wireless Controllers
Cisco Catalyst 9800 Wireless Controllers for Cloud

Remediation

Refer to Cisco Advisory for patch, upgrade or suggested workaround information.

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-ipv6-dos-NMYeCnZv

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