QID 317052

Date Published: 2021-09-27

QID 317052: Cisco Internetwork Operating System (IOS) XE Software for Catalyst 9800 Series Wireless Controllers Internet Protocol (IPv6) Denial of Service (DoS) Vulnerability (cisco-sa-ewlc-ipv6-dos-NMYeCnZv)

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.

Affected Products
Catalyst 9800 Wireless Controllers
Catalyst 9800 Wireless Controllers for Cloud

QID Detection Logic (Authenticated):
The check matches Cisco IOS XE version retrieved via Unix Auth using "show version" command.
QID Detection Logic (Unauthenticated):
The check matches Cisco IOS XE version retrieved via SNMP or TCP/IP Fingerprint or NTP or Telnet.

A successful exploit could allow the attacker to cause traffic drops in the affected VLAN, thus triggering the DoS condition.

  • CVSS V3 rated as High - 6.3 severity.
  • CVSS V2 rated as High - 7.5 severity.
    • Solution

    Customers are advised to refer to cisco-sa-ewlc-ipv6-dos-NMYeCnZv for more information.

    Vendor References

    CVEs related to QID 317052

    CVE-2021-34767 |
    Software Advisories
    Advisory ID Software Component Link
    cisco-sa-ewlc-ipv6-dos-NMYeCnZv URL Logo tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-ipv6-dos-NMYeCnZv
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