CVE-2020-3221
highpriority · track · 35EPSS 0.015 · 74 %ileEURUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed16.10.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1bcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1ecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.11.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.11.99SWcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (41)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-iosxe-fnfv9-dos-HND6Fc9uCisco IOS XE Software Flexible NetFlow Version 9 Denial of Service Vulnerability2020-06-03csaf · cisco_csafUS
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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-fnfv9-dos-HND6Fc9u ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-fnfv9-dos-HND6Fc9u"] This advisory is part of the June 3, 2020, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes 23 Cisco Security Advisories that describe 25 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: June 2020 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication [" https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-73388"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2020-3221cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-fnfv9-dos-HND6Fc9ucnnvd
- https://vigilance.fr/vulnerability/Cisco-IOS-XE-multiple-vulnerabilities-32421cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.1941/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-fnfv9-dos-HND6Fc9uenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-fnfv9-dos-HND6Fc9uPatchVendor Advisorynvd
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