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CVE-2020-3221

Cisco IOS XE Software Flexible NetFlow Version 9 Denial of Service Vulnerability

High8.6EPSS 1.5%
Published
Updated
Reserved
Assigned by
cisco

Description

A vulnerability in the Flexible NetFlow Version 9 packet processor of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper validation of parameters in a Flexible NetFlow Version 9 record. An attacker could exploit this vulnerability by sending a malformed Flexible NetFlow Version 9 packet to the Control and Provisioning of Wireless Access Points (CAPWAP) data port of an affected device. An exploit could allow the attacker to trigger an infinite loop, resulting in a process crash that would cause a reload of the device.

Scores

CVSS scores of CVE-2020-3221, by who scored it
Scored byCVSSScoreVector
ciscoCNA (assigner)3.0High8.6CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVDNVD · Modified3.1High8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS (exploitation in 30 days)
1.5% · top 25% of all CVEs (6 Nov 2026)
CISA SSVC
Exploitation: none · Automatable: yes · Technical impact: partial
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The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.

Weakness

Affected products

What to do

Exploitation: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

References (1)

Sources

The same CVE in the primary databases and aggregators, to check against.

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Record last updated .