CVE-2021-34697

published 2021-09-23

CVE-2021-34697: A vulnerability in the Protection Against Distributed Denial of Service Attacks feature of Cisco IOS XE Software could allow an unauthenticated, remote…

Priority P3 47 high 8.6 CVSS 3.1

AV N AC L PR N UI N S C C N I N A H

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
cisco	cisco_ios_xe_software	—	—
cisco	ios_xe	—	—
cisco	ios_xe	>= 17.3.1 < 17.3.3	17.3.3

CVSS provenance

nvd v3.1 8.6 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

nvd v2.0 5.0 MEDIUM AV:N/AC:L/Au:N/C:N/I:N/A:P

vendor_cisco 5.8 MEDIUM

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