CVE-2021-34697

Cisco IOS XE Software Protection Against Distributed Denial of Service Attacks Feature Vulnerability

Description

A vulnerability in the Protection Against Distributed Denial of Service Attacks feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct denial of service (DoS) attacks to or through the affected device. This vulnerability is due to incorrect programming of the half-opened connections limit, TCP SYN flood limit, or TCP SYN cookie features when the features are configured in vulnerable releases of Cisco IOS XE Software. An attacker could exploit this vulnerability by attempting to flood traffic to or through the affected device. A successful exploit could allow the attacker to initiate a DoS attack to or through an affected device.

Category

5.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.47%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XE Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-34697?
CVE-2021-34697 has been scored as a medium severity vulnerability.
How to fix CVE-2021-34697?
To fix CVE-2021-34697, 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-2021-34697 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34697 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-2021-34697?
CVE-2021-34697 affects Cisco Cisco IOS XE Software.
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