CVE-2021-34697
5.8 · MEDIUMOverview
CVE-2021-34697 is a medium-severity vulnerability affecting cisco ios_xe. It was published on September 23, 2021 and has a CVSS 3.1 base score of 5.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from cisco. Update ios_xe to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| cisco | ios_xe | >= 17.3.1, < 17.3.3 | Affected |
Frequently Asked Questions
What is CVE-2021-34697?
CVE-2021-34697 is a medium-severity vulnerability affecting cisco ios_xe. It was published on September 23, 2021 and has a CVSS 3.1 base score of 5.8 (MEDIUM).
How severe is CVE-2021-34697?
This vulnerability has a CVSS 3.1 base score of 5.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-34697?
Check the references section for vendor advisories and patches from cisco. Update ios_xe to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-34697?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-34697 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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