CVE-2021-1621

Cisco IOS XE Software Interface Queue Wedge Denial of Service Vulnerability

Description

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.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
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-quewedge-69BsHUBW patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-1621?
CVE-2021-1621 has been scored as a high severity vulnerability.
How to fix CVE-2021-1621?
To fix CVE-2021-1621, 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-2021-1621 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1621 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-2021-1621?
CVE-2021-1621 affects Cisco Cisco IOS XE Software.
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