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Case File

CVE-2021-34697

MEDIUM · CVSS 5.8 EPSS 1.33% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-09-23 · Last synced 2026-08-04

CyberRota Analysis

This is a medium severity vulnerability with a CVSS score of 5.8. It affects Cisco. Public exploit code or proof-of-concept references have been detected in its references. It may be remotely exploitable. It may lead to a denial-of-service condition.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-34697
Severity
MEDIUM
CVSS
5.8
EPSS
1.33%
Cisco

Original NVD 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.

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