CVE-2021-1611

Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers EoGRE Denial of Service Vulnerability

Description

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.48%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XE Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-gre-6u4ELzAT patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-1611?
CVE-2021-1611 has been scored as a high severity vulnerability.
How to fix CVE-2021-1611?
To fix CVE-2021-1611, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-1611 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1611 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1611?
CVE-2021-1611 affects Cisco Cisco IOS XE Software.
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