CVE-2021-1611: Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers EoGRE Denial of Service Vulnerability

Published Sep 23, 2021
·
Updated

A vulnerability in Ethernet over GRE (EoGRE) packet processing of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9800 Family Wireless Controller, Embedded Wireless Controller, and Embedded Wireless on Catalyst 9000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper processing of malformed EoGRE packets. An attacker could exploit this vulnerability by sending malicious packets to the affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Affected Software

8 affected components
Cisco IOS XE<17.3.1
Cisco Catalyst 9800
Cisco Catalyst 9800-40
Cisco Catalyst 9800-80
Cisco Catalyst 9800-cl
Cisco Catalyst 9800-l
Cisco Catalyst 9800-l-c
Cisco Catalyst 9800-l-f

Event History

Sep 23, 2021
CVE Published
via MITRE·02:30 AM
Data Sourced
via MITRE·02:30 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2021-1611?

CVE-2021-1611 is a vulnerability in Ethernet over GRE (EoGRE) packet processing of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9800 Family Wireless Controller, Embedded Wireless Controller, and Embedded Wireless on Catalyst 9000 Series Switches.

2

What is the severity of CVE-2021-1611?

The severity of CVE-2021-1611 is high with a CVSSv3 score of 8.6.

3

Which software is affected by CVE-2021-1611?

Cisco IOS XE versions up to and exclusive to 17.3.1 are affected by CVE-2021-1611.

4

How can an attacker exploit CVE-2021-1611?

An unauthenticated, remote attacker can exploit CVE-2021-1611 by sending malicious Ethernet over GRE (EoGRE) packets to the affected devices.

5

How can CVE-2021-1611 be fixed?

To fix CVE-2021-1611, it is recommended to upgrade to a fixed version of Cisco IOS XE software.

Contact

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